fix if/else bug in _mesa_ProgramEnvParameter4fARB (fdo bug 1645)
diff --git a/src/mesa/shader/arbprogram.c b/src/mesa/shader/arbprogram.c
index 79615d6..ad8683f 100644
--- a/src/mesa/shader/arbprogram.c
+++ b/src/mesa/shader/arbprogram.c
@@ -265,7 +265,7 @@
       }
       ASSIGN_4V(ctx->FragmentProgram.Parameters[index], x, y, z, w);
    }
-   if (target == GL_VERTEX_PROGRAM_ARB
+   else if (target == GL_VERTEX_PROGRAM_ARB
        && ctx->Extensions.ARB_vertex_program) {
       if (index >= ctx->Const.MaxVertexProgramEnvParams) {
          _mesa_error(ctx, GL_INVALID_VALUE, "glProgramEnvParameter(index)");
@@ -325,7 +325,7 @@
       }
       COPY_4V(params, ctx->FragmentProgram.Parameters[index]);
    }
-   if (target == GL_VERTEX_PROGRAM_ARB
+   else if (target == GL_VERTEX_PROGRAM_ARB
        && ctx->Extensions.ARB_vertex_program) {
       if (index >= ctx->Const.MaxVertexProgramEnvParams) {
          _mesa_error(ctx, GL_INVALID_VALUE, "glGetProgramEnvParameter(index)");