diff --git a/src/mesa/main/context.c b/src/mesa/main/context.c
index 7b8d934..b905334 100755
--- a/src/mesa/main/context.c
+++ b/src/mesa/main/context.c
@@ -150,8 +150,6 @@
 /* ubyte -> float conversion */
 GLfloat _mesa_ubyte_to_float_color_tab[256];
 
-static void
-free_shared_state( GLcontext *ctx, struct gl_shared_state *ss );
 
 
 /**
@@ -423,12 +421,14 @@
 #endif
 
 #if FEATURE_ARB_vertex_program
-   ss->DefaultVertexProgram = ctx->Driver.NewProgram(ctx, GL_VERTEX_PROGRAM_ARB, 0);
+   ss->DefaultVertexProgram = (struct gl_vertex_program *)
+      ctx->Driver.NewProgram(ctx, GL_VERTEX_PROGRAM_ARB, 0);
    if (!ss->DefaultVertexProgram)
       goto cleanup;
 #endif
 #if FEATURE_ARB_fragment_program
-   ss->DefaultFragmentProgram = ctx->Driver.NewProgram(ctx, GL_FRAGMENT_PROGRAM_ARB, 0);
+   ss->DefaultFragmentProgram = (struct gl_fragment_program *)
+      ctx->Driver.NewProgram(ctx, GL_FRAGMENT_PROGRAM_ARB, 0);
    if (!ss->DefaultFragmentProgram)
       goto cleanup;
 #endif
@@ -513,12 +513,10 @@
       _mesa_DeleteHashTable(ss->Programs);
 #endif
 #if FEATURE_ARB_vertex_program
-   if (ss->DefaultVertexProgram)
-      ctx->Driver.DeleteProgram(ctx, ss->DefaultVertexProgram);
+   _mesa_reference_vertprog(ctx, &ss->DefaultVertexProgram, NULL);
 #endif
 #if FEATURE_ARB_fragment_program
-   if (ss->DefaultFragmentProgram)
-      ctx->Driver.DeleteProgram(ctx, ss->DefaultFragmentProgram);
+   _mesa_reference_fragprog(ctx, &ss->DefaultFragmentProgram, NULL);
 #endif
 #if FEATURE_ATI_fragment_shader
    if (ss->DefaultFragmentShader)
@@ -695,10 +693,10 @@
    _mesa_DeleteHashTable(ss->Programs);
 #endif
 #if FEATURE_ARB_vertex_program
-   ctx->Driver.DeleteProgram(ctx, ss->DefaultVertexProgram);
+   _mesa_reference_vertprog(ctx, &ss->DefaultVertexProgram, NULL);
 #endif
 #if FEATURE_ARB_fragment_program
-   ctx->Driver.DeleteProgram(ctx, ss->DefaultFragmentProgram);
+   _mesa_reference_fragprog(ctx, &ss->DefaultFragmentProgram, NULL);
 #endif
 
 #if FEATURE_ATI_fragment_shader
@@ -1190,6 +1188,14 @@
       _mesa_unreference_framebuffer(&ctx->ReadBuffer);
    }
 
+   _mesa_reference_vertprog(ctx, &ctx->VertexProgram.Current, NULL);
+   _mesa_reference_vertprog(ctx, &ctx->VertexProgram._Current, NULL);
+   _mesa_reference_vertprog(ctx, &ctx->VertexProgram._TnlProgram, NULL);
+
+   _mesa_reference_fragprog(ctx, &ctx->FragmentProgram.Current, NULL);
+   _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._Current, NULL);
+   _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._TexEnvProgram, NULL);
+
    _mesa_free_lighting_data( ctx );
    _mesa_free_eval_data( ctx );
    _mesa_free_texture_data( ctx );
diff --git a/src/mesa/main/mtypes.h b/src/mesa/main/mtypes.h
index 50b22d2..463142f 100644
--- a/src/mesa/main/mtypes.h
+++ b/src/mesa/main/mtypes.h
@@ -2203,10 +2203,10 @@
    /*@{*/
    struct _mesa_HashTable *Programs; /**< All vertex/fragment programs */
 #if FEATURE_ARB_vertex_program
-   struct gl_program *DefaultVertexProgram;
+   struct gl_vertex_program *DefaultVertexProgram;
 #endif
 #if FEATURE_ARB_fragment_program
-   struct gl_program *DefaultFragmentProgram;
+   struct gl_fragment_program *DefaultFragmentProgram;
 #endif
    /*@}*/
 
diff --git a/src/mesa/main/state.c b/src/mesa/main/state.c
index 0b1c56f..90379a1 100644
--- a/src/mesa/main/state.c
+++ b/src/mesa/main/state.c
@@ -982,16 +982,20 @@
 #endif
    if (shProg && shProg->LinkStatus && shProg->FragmentProgram) {
       /* user-defined fragment shader */
-      ctx->FragmentProgram._Current = shProg->FragmentProgram;
+      _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._Current,
+                               shProg->FragmentProgram);
    }
    else if (ctx->FragmentProgram._Enabled) {
       /* use user-defined fragment program */
-      ctx->FragmentProgram._Current = ctx->FragmentProgram.Current;
+      _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._Current,
+                               ctx->FragmentProgram.Current);
    }
    else if (ctx->FragmentProgram._MaintainTexEnvProgram) {
       /* fragment program generated from fixed-function state */
-      ctx->FragmentProgram._Current = _mesa_get_fixed_func_fragment_program(ctx);
-      ctx->FragmentProgram._TexEnvProgram = ctx->FragmentProgram._Current;
+      _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._Current,
+                               _mesa_get_fixed_func_fragment_program(ctx));
+      _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._TexEnvProgram,
+                               ctx->FragmentProgram._Current);
 
       /* XXX get rid of this confusing stuff someday? */
       ctx->FragmentProgram._Active = ctx->FragmentProgram._Enabled;
@@ -1000,7 +1004,7 @@
    }
    else {
       /* no fragment program */
-      ctx->FragmentProgram._Current = NULL;
+      _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._Current, NULL);
    }
 
    if (ctx->FragmentProgram._Current != prevFP && ctx->Driver.BindProgram) {
@@ -1013,29 +1017,33 @@
     **/
 #if 1
    /* XXX get rid of this someday? */
-   ctx->VertexProgram._TnlProgram = NULL;
+   _mesa_reference_vertprog(ctx, &ctx->VertexProgram._TnlProgram, NULL);
 #endif
    if (shProg && shProg->LinkStatus && shProg->VertexProgram) {
       /* user-defined vertex shader */
-      ctx->VertexProgram._Current = shProg->VertexProgram;
+      _mesa_reference_vertprog(ctx, &ctx->VertexProgram._Current,
+                               shProg->VertexProgram);
    }
    else if (ctx->VertexProgram._Enabled) {
       /* use user-defined vertex program */
-      ctx->VertexProgram._Current = ctx->VertexProgram.Current;
+      _mesa_reference_vertprog(ctx, &ctx->VertexProgram._Current,
+                               ctx->VertexProgram.Current);
    }
    else if (ctx->VertexProgram._MaintainTnlProgram) {
       /* vertex program generated from fixed-function state */
-      ctx->VertexProgram._Current = _mesa_get_fixed_func_vertex_program(ctx);
-      ctx->VertexProgram._TnlProgram = ctx->VertexProgram._Current;
+      _mesa_reference_vertprog(ctx, &ctx->VertexProgram._Current,
+                               _mesa_get_fixed_func_vertex_program(ctx));
+      _mesa_reference_vertprog(ctx, &ctx->VertexProgram._TnlProgram,
+                               ctx->VertexProgram._Current);
    }
    else {
       /* no vertex program / used fixed-function code */
-      ctx->VertexProgram._Current = NULL;
+      _mesa_reference_vertprog(ctx, &ctx->VertexProgram._Current, NULL);
    }
 
    if (ctx->VertexProgram._Current != prevVP && ctx->Driver.BindProgram) {
       ctx->Driver.BindProgram(ctx, GL_VERTEX_PROGRAM_ARB,
-                              (struct gl_program *) ctx->VertexProgram._Current);
+                           (struct gl_program *) ctx->VertexProgram._Current);
    }
 }
 
diff --git a/src/mesa/shader/prog_cache.c b/src/mesa/shader/prog_cache.c
index dd0241e..36a2537 100644
--- a/src/mesa/shader/prog_cache.c
+++ b/src/mesa/shader/prog_cache.c
@@ -30,6 +30,7 @@
 #include "main/mtypes.h"
 #include "main/imports.h"
 #include "shader/prog_cache.h"
+#include "shader/program.h"
 
 
 struct cache_item
@@ -109,7 +110,7 @@
       for (c = cache->items[i]; c; c = next) {
 	 next = c->next;
 	 _mesa_free(c->key);
-	 ctx->Driver.DeleteProgram(ctx, c->program);
+         _mesa_reference_program(ctx, &c->program, NULL);
 	 _mesa_free(c);
       }
       cache->items[i] = NULL;
@@ -177,7 +178,7 @@
    c->key = _mesa_malloc(keysize);
    memcpy(c->key, key, keysize);
 
-   c->program = program;
+   c->program = program;  /* no refcount change */
 
    if (cache->n_items > cache->size * 1.5) {
       if (cache->size < 1000)
diff --git a/src/mesa/shader/program.c b/src/mesa/shader/program.c
index 0ed7f83..9a23c5d 100644
--- a/src/mesa/shader/program.c
+++ b/src/mesa/shader/program.c
@@ -60,9 +60,9 @@
    ctx->VertexProgram.Enabled = GL_FALSE;
    ctx->VertexProgram.PointSizeEnabled = GL_FALSE;
    ctx->VertexProgram.TwoSideEnabled = GL_FALSE;
-   ctx->VertexProgram.Current = (struct gl_vertex_program *) ctx->Shared->DefaultVertexProgram;
+   _mesa_reference_vertprog(ctx, &ctx->VertexProgram.Current,
+                            ctx->Shared->DefaultVertexProgram);
    assert(ctx->VertexProgram.Current);
-   ctx->VertexProgram.Current->Base.RefCount++;
    for (i = 0; i < MAX_NV_VERTEX_PROGRAM_PARAMS / 4; i++) {
       ctx->VertexProgram.TrackMatrix[i] = GL_NONE;
       ctx->VertexProgram.TrackMatrixTransform[i] = GL_IDENTITY_NV;
@@ -72,9 +72,9 @@
 
 #if FEATURE_NV_fragment_program || FEATURE_ARB_fragment_program
    ctx->FragmentProgram.Enabled = GL_FALSE;
-   ctx->FragmentProgram.Current = (struct gl_fragment_program *) ctx->Shared->DefaultFragmentProgram;
+   _mesa_reference_fragprog(ctx, &ctx->FragmentProgram.Current,
+                            ctx->Shared->DefaultFragmentProgram);
    assert(ctx->FragmentProgram.Current);
-   ctx->FragmentProgram.Current->Base.RefCount++;
    ctx->FragmentProgram.Cache = _mesa_new_program_cache();
 #endif
 
@@ -96,19 +96,11 @@
 _mesa_free_program_data(GLcontext *ctx)
 {
 #if FEATURE_NV_vertex_program || FEATURE_ARB_vertex_program
-   if (ctx->VertexProgram.Current) {
-      ctx->VertexProgram.Current->Base.RefCount--;
-      if (ctx->VertexProgram.Current->Base.RefCount <= 0)
-         ctx->Driver.DeleteProgram(ctx, &(ctx->VertexProgram.Current->Base));
-   }
+   _mesa_reference_vertprog(ctx, &ctx->VertexProgram.Current, NULL);
    _mesa_delete_program_cache(ctx, ctx->VertexProgram.Cache);
 #endif
 #if FEATURE_NV_fragment_program || FEATURE_ARB_fragment_program
-   if (ctx->FragmentProgram.Current) {
-      ctx->FragmentProgram.Current->Base.RefCount--;
-      if (ctx->FragmentProgram.Current->Base.RefCount <= 0)
-         ctx->Driver.DeleteProgram(ctx, &(ctx->FragmentProgram.Current->Base));
-   }
+   _mesa_reference_fragprog(ctx, &ctx->FragmentProgram.Current, NULL);
    _mesa_delete_program_cache(ctx, ctx->FragmentProgram.Cache);
 #endif
    /* XXX probably move this stuff */
@@ -326,6 +318,59 @@
 
 
 /**
+ * Reference counting for vertex/fragment programs
+ */
+void
+_mesa_reference_program(GLcontext *ctx,
+                        struct gl_program **ptr,
+                        struct gl_program *prog)
+{
+   assert(ptr);
+   if (*ptr && prog) {
+      /* sanity check */
+      ASSERT((*ptr)->Target == prog->Target);
+   }
+   if (*ptr == prog) {
+      return;  /* no change */
+   }
+   if (*ptr) {
+      GLboolean deleteFlag;
+
+      /*_glthread_LOCK_MUTEX((*ptr)->Mutex);*/
+#if 0
+      printf("Program %p %u 0x%x  Refcount-- to %d\n",
+             *ptr, (*ptr)->Id, (*ptr)->Target, (*ptr)->RefCount - 1);
+#endif
+      ASSERT((*ptr)->RefCount > 0);
+      (*ptr)->RefCount--;
+
+      deleteFlag = ((*ptr)->RefCount == 0);
+      /*_glthread_UNLOCK_MUTEX((*ptr)->Mutex);*/
+      
+      if (deleteFlag) {
+         ASSERT(ctx);
+         ctx->Driver.DeleteProgram(ctx, *ptr);
+      }
+
+      *ptr = NULL;
+   }
+
+   assert(!*ptr);
+   if (prog) {
+      /*_glthread_LOCK_MUTEX(prog->Mutex);*/
+      prog->RefCount++;
+#if 0
+      printf("Program %p %u 0x%x  Refcount++ to %d\n",
+             prog, prog->Id, prog->Target, prog->RefCount);
+#endif
+      /*_glthread_UNLOCK_MUTEX(prog->Mutex);*/
+   }
+
+   *ptr = prog;
+}
+
+
+/**
  * Return a copy of a program.
  * XXX Problem here if the program object is actually OO-derivation
  * made by a device driver.
@@ -340,8 +385,9 @@
       return NULL;
 
    assert(clone->Target == prog->Target);
+   assert(clone->RefCount == 1);
+
    clone->String = (GLubyte *) _mesa_strdup((char *) prog->String);
-   clone->RefCount = 1;
    clone->Format = prog->Format;
    clone->Instructions = _mesa_alloc_instructions(prog->NumInstructions);
    if (!clone->Instructions) {
@@ -704,9 +750,9 @@
       /* Bind a default program */
       newProg = NULL;
       if (target == GL_VERTEX_PROGRAM_ARB) /* == GL_VERTEX_PROGRAM_NV */
-         newProg = ctx->Shared->DefaultVertexProgram;
+         newProg = &ctx->Shared->DefaultVertexProgram->Base;
       else
-         newProg = ctx->Shared->DefaultFragmentProgram;
+         newProg = &ctx->Shared->DefaultFragmentProgram->Base;
    }
    else {
       /* Bind a user program */
@@ -734,26 +780,16 @@
       return;
    }
 
-   /* unbind/delete oldProg */
-   if (curProg->Id != 0) {
-      /* decrement refcount on previously bound fragment program */
-      curProg->RefCount--;
-      /* and delete if refcount goes below one */
-      if (curProg->RefCount <= 0) {
-         /* the program ID was already removed from the hash table */
-         ctx->Driver.DeleteProgram(ctx, curProg);
-      }
-   }
-
    /* bind newProg */
    if (target == GL_VERTEX_PROGRAM_ARB) { /* == GL_VERTEX_PROGRAM_NV */
-      ctx->VertexProgram.Current = (struct gl_vertex_program *) newProg;
+      _mesa_reference_vertprog(ctx, &ctx->VertexProgram.Current,
+                               (struct gl_vertex_program *) newProg);
    }
    else if (target == GL_FRAGMENT_PROGRAM_NV ||
             target == GL_FRAGMENT_PROGRAM_ARB) {
-      ctx->FragmentProgram.Current = (struct gl_fragment_program *) newProg;
+      _mesa_reference_fragprog(ctx, &ctx->FragmentProgram.Current,
+                               (struct gl_fragment_program *) newProg);
    }
-   newProg->RefCount++;
 
    /* Never null pointers */
    ASSERT(ctx->VertexProgram.Current);
@@ -811,10 +847,7 @@
             }
             /* The ID is immediately available for re-use now */
             _mesa_HashRemove(ctx->Shared->Programs, ids[i]);
-            prog->RefCount--;
-            if (prog->RefCount <= 0) {
-               ctx->Driver.DeleteProgram(ctx, prog);
-            }
+            _mesa_reference_program(ctx, &prog, NULL);
          }
       }
    }
diff --git a/src/mesa/shader/program.h b/src/mesa/shader/program.h
index 414a57d..08fe576 100644
--- a/src/mesa/shader/program.h
+++ b/src/mesa/shader/program.h
@@ -83,6 +83,28 @@
 extern struct gl_program *
 _mesa_lookup_program(GLcontext *ctx, GLuint id);
 
+extern void
+_mesa_reference_program(GLcontext *ctx,
+                        struct gl_program **ptr,
+                        struct gl_program *prog);
+
+static INLINE void
+_mesa_reference_vertprog(GLcontext *ctx,
+                         struct gl_vertex_program **ptr,
+                         struct gl_vertex_program *prog)
+{
+   _mesa_reference_program(ctx, (struct gl_program **) ptr,
+                           (struct gl_program *) prog);
+}
+
+static INLINE void
+_mesa_reference_fragprog(GLcontext *ctx,
+                         struct gl_fragment_program **ptr,
+                         struct gl_fragment_program *prog)
+{
+   _mesa_reference_program(ctx, (struct gl_program **) ptr,
+                           (struct gl_program *) prog);
+}
 
 extern struct gl_program *
 _mesa_clone_program(GLcontext *ctx, const struct gl_program *prog);
diff --git a/src/mesa/shader/shader_api.c b/src/mesa/shader/shader_api.c
index 9c419c9..f12fa28 100644
--- a/src/mesa/shader/shader_api.c
+++ b/src/mesa/shader/shader_api.c
@@ -80,8 +80,7 @@
        * original/unlinked program.
        */
       shProg->VertexProgram->Base.Parameters = NULL;
-      ctx->Driver.DeleteProgram(ctx, &shProg->VertexProgram->Base);
-      shProg->VertexProgram = NULL;
+      _mesa_reference_vertprog(ctx, &shProg->VertexProgram, NULL);
    }
 
    if (shProg->FragmentProgram) {
@@ -89,8 +88,7 @@
        * original/unlinked program.
        */
       shProg->FragmentProgram->Base.Parameters = NULL;
-      ctx->Driver.DeleteProgram(ctx, &shProg->FragmentProgram->Base);
-      shProg->FragmentProgram = NULL;
+      _mesa_reference_fragprog(ctx, &shProg->FragmentProgram, NULL);
    }
 
    if (shProg->Uniforms) {
diff --git a/src/mesa/shader/slang/slang_link.c b/src/mesa/shader/slang/slang_link.c
index addff20..ae58155 100644
--- a/src/mesa/shader/slang/slang_link.c
+++ b/src/mesa/shader/slang/slang_link.c
@@ -410,19 +410,19 @@
     * changing src/dst registers after merging the uniforms and varying vars.
     */
    if (vertProg) {
-      shProg->VertexProgram
-         = vertex_program(_mesa_clone_program(ctx, &vertProg->Base));
+      _mesa_reference_vertprog(ctx, &shProg->VertexProgram,
+                               vertex_program(_mesa_clone_program(ctx, &vertProg->Base)));
    }
    else {
-      shProg->VertexProgram = NULL;
+      _mesa_reference_vertprog(ctx, &shProg->VertexProgram, NULL);
    }
 
    if (fragProg) {
-      shProg->FragmentProgram
-         = fragment_program(_mesa_clone_program(ctx, &fragProg->Base));
+      _mesa_reference_fragprog(ctx, &shProg->FragmentProgram,
+                               fragment_program(_mesa_clone_program(ctx, &fragProg->Base)));
    }
    else {
-      shProg->FragmentProgram = NULL;
+      _mesa_reference_fragprog(ctx, &shProg->FragmentProgram, NULL);
    }
 
    /* link varying vars */
diff --git a/src/mesa/state_tracker/st_atom_shader.c b/src/mesa/state_tracker/st_atom_shader.c
index 652500f..7745591 100644
--- a/src/mesa/state_tracker/st_atom_shader.c
+++ b/src/mesa/state_tracker/st_atom_shader.c
@@ -39,6 +39,7 @@
 
 #include "main/imports.h"
 #include "main/mtypes.h"
+#include "shader/program.h"
 
 #include "pipe/p_context.h"
 #include "pipe/p_shader_tokens.h"
@@ -264,14 +265,16 @@
     */
    assert(st->ctx->VertexProgram._Current);
    stvp = st_vertex_program(st->ctx->VertexProgram._Current);
+   assert(stvp->Base.Base.Target == GL_VERTEX_PROGRAM_ARB);
 
    assert(st->ctx->FragmentProgram._Current);
    stfp = st_fragment_program(st->ctx->FragmentProgram._Current);
+   assert(stfp->Base.Base.Target == GL_FRAGMENT_PROGRAM_ARB);
 
    xvp = find_translated_vp(st, stvp, stfp);
 
-   st->vp = stvp;
-   st->fp = stfp;
+   st_reference_vertprog(st, &st->vp, stvp);
+   st_reference_fragprog(st, &st->fp, stfp);
 
    cso_set_vertex_shader_handle(st->cso_context, stvp->driver_shader);
    cso_set_fragment_shader_handle(st->cso_context, stfp->driver_shader);
diff --git a/src/mesa/state_tracker/st_context.c b/src/mesa/state_tracker/st_context.c
index c900064..8db55a1 100644
--- a/src/mesa/state_tracker/st_context.c
+++ b/src/mesa/state_tracker/st_context.c
@@ -158,6 +158,9 @@
 {
    uint i;
 
+   st_reference_fragprog(st, &st->fp, NULL);
+   st_reference_vertprog(st, &st->vp, NULL);
+
    draw_destroy(st->draw);
    st_destroy_atoms( st );
    st_destroy_draw( st );
diff --git a/src/mesa/state_tracker/st_program.h b/src/mesa/state_tracker/st_program.h
index d8f26da..bf07a50 100644
--- a/src/mesa/state_tracker/st_program.h
+++ b/src/mesa/state_tracker/st_program.h
@@ -34,7 +34,8 @@
 #ifndef ST_PROGRAM_H
 #define ST_PROGRAM_H
 
-#include "mtypes.h"
+#include "main/mtypes.h"
+#include "shader/program.h"
 #include "pipe/p_shader_tokens.h"
 
 
@@ -115,6 +116,27 @@
 }
 
 
+static INLINE void
+st_reference_vertprog(struct st_context *st,
+                      struct st_vertex_program **ptr,
+                      struct st_vertex_program *prog)
+{
+   _mesa_reference_program(st->ctx,
+                           (struct gl_program **) ptr,
+                           (struct gl_program *) prog);
+}
+
+static INLINE void
+st_reference_fragprog(struct st_context *st,
+                      struct st_fragment_program **ptr,
+                      struct st_fragment_program *prog)
+{
+   _mesa_reference_program(st->ctx,
+                           (struct gl_program **) ptr,
+                           (struct gl_program *) prog);
+}
+
+
 extern void
 st_translate_fragment_program(struct st_context *st,
                               struct st_fragment_program *fp,