diff --git a/opengl/tools/glgen/specs/jsr239/glspec-1.1extpack b/opengl/tools/glgen/specs/jsr239/glspec-1.1extpack
index ca9e6d2..d6012d9 100644
--- a/opengl/tools/glgen/specs/jsr239/glspec-1.1extpack
+++ b/opengl/tools/glgen/specs/jsr239/glspec-1.1extpack
@@ -7,14 +7,14 @@
 GLint glCheckFramebufferStatusOES ( GLint target )
 void glCompressedTexImage2D ( GLenum target, GLint level, GLenum internalformat, GLsizei width, GLsizei height, GLint border, GLsizei imageSize, const GLvoid *data )
 void glCopyTexImage2D ( GLint target, GLint level, GLint internalformat, GLint x, GLint y, GLint width, GLint height, GLint border )
-void glDeleteFramebuffersOES ( GLint n, GLint *framebuffers )
-void glDeleteRenderbuffersOES ( GLint n, GLint *renderbuffers )
+void glDeleteFramebuffersOES ( GLint n, GLuint *framebuffers )
+void glDeleteRenderbuffersOES ( GLint n, GLuint *renderbuffers )
 void glEnable ( GLint cap )
 void glFramebufferRenderbufferOES ( GLint target, GLint attachment, GLint renderbuffertarget, GLint renderbuffer )
 void glFramebufferTexture2DOES ( GLint target, GLint attachment, GLint textarget, GLint texture, GLint level )
 void glGenerateMipmapOES ( GLint target )
-void glGenFramebuffersOES ( GLint n, GLint *framebuffers )
-void glGenRenderbuffersOES ( GLint n, GLint *renderbuffers )
+void glGenFramebuffersOES ( GLint n, GLuint *framebuffers )
+void glGenRenderbuffersOES ( GLint n, GLuint *renderbuffers )
 void glGetFramebufferAttachmentParameterivOES ( GLint target, GLint attachment, GLint pname, GLint *params )
 void glGetIntegerv ( GLint pname, GLint *params )
 void glGetRenderbufferParameterivOES ( GLint target, GLint pname, GLint *params )
diff --git a/opengl/tools/glgen/specs/jsr239/glspec-checks b/opengl/tools/glgen/specs/jsr239/glspec-checks
index c28e403..9f8a793 100644
--- a/opengl/tools/glgen/specs/jsr239/glspec-checks
+++ b/opengl/tools/glgen/specs/jsr239/glspec-checks
@@ -29,28 +29,28 @@
 glDrawTexivOES check coords 5
 glDrawTexsvOES check coords 5
 glDrawTexxvOES check coords 5
-glBindFramebufferOES unsupported
-glBindRenderbufferOES unsupported
-glBlendEquation unsupported
-glBlendEquationSeparate unsupported
-glBlendFuncSeparate unsupported
-glCheckFramebufferStatusOES unsupported return 0
-glDeleteFramebuffersOES unsupported
-glDeleteRenderbuffersOES unsupported
-glFramebufferRenderbufferOES unsupported
-glFramebufferStorageOES unsupported
-glFramebufferTexture2DOES unsupported
-glGenFramebuffersOES unsupported
-glGenRenderbuffersOES unsupported
-glGenerateMipmapOES unsupported
+glBindFramebufferOES requires OES_framebuffer_object
+glBindRenderbufferOES requires OES_framebuffer_object
+glBlendEquation requires OES_blend_subtract
+glBlendEquationSeparate requires OES_blend_equation_separate
+glBlendFuncSeparate requires OES_blend_equation_separate
+glCheckFramebufferStatusOES requires OES_framebuffer_object return 0
+glDeleteFramebuffersOES requires OES_framebuffer_object check framebuffers n
+glDeleteRenderbuffersOES requires OES_framebuffer_object check renderbuffers n
+glFramebufferRenderbufferOES requires OES_framebuffer_object
+glFramebufferStorageOES requires OES_framebuffer_object
+glFramebufferTexture2DOES requires OES_framebuffer_object
+glGenFramebuffersOES requires OES_framebuffer_object check framebuffers n
+glGenRenderbuffersOES requires OES_framebuffer_object check renderbuffers n
+glGenerateMipmapOES requires OES_framebuffer_object
+glGetFramebufferAttachmentParameterivOES requires OES_framebuffer_object
+glGetRenderbufferParameterivOES requires OES_framebuffer_object
+glIsFramebufferOES requires OES_framebuffer_object return JNI_FALSE
+glIsRenderbufferOES requires OES_framebuffer_object return JNI_FALSE
+glRenderbufferStorageOES requires OES_framebuffer_object
+glGetTexGen requires OES_texture_cube_map
+glTexGen requires OES_texture_cube_map
+glTexGenf requires OES_texture_cube_map
+glTexGeni requires OES_texture_cube_map
+glTexGenx requires OES_texture_cube_map
 glGetBufferParameter unsupported
-glGetFramebufferAttachmentParameterivOES unsupported
-glGetRenderbufferParameterivOES unsupported
-glGetTexGen unsupported
-glIsFramebufferOES unsupported return JNI_FALSE
-glIsRenderbufferOES unsupported return JNI_FALSE
-glRenderbufferStorageOES unsupported return false
-glTexGen unsupported
-glTexGenf unsupported
-glTexGeni unsupported
-glTexGenx unsupported
diff --git a/opengl/tools/glgen/src/JniCodeEmitter.java b/opengl/tools/glgen/src/JniCodeEmitter.java
index e79170a..2db4e8d 100644
--- a/opengl/tools/glgen/src/JniCodeEmitter.java
+++ b/opengl/tools/glgen/src/JniCodeEmitter.java
@@ -211,6 +211,8 @@
                     index += 5;
                 } else if (checks[index].equals("unsupported")) {
                     index += 1;
+                } else if (checks[index].equals("requires")) {
+                    index += 2;
                 } else if (checks[index].equals("nullAllowed")) {
                     return true;
                 } else {
@@ -243,6 +245,8 @@
                     index += 5;
                 } else if (checks[index].equals("unsupported")) {
                     index += 1;
+                } else if (checks[index].equals("requires")) {
+                    index += 2;
                 } else if (checks[index].equals("nullAllowed")) {
                     index += 1;
                 } else {
@@ -263,6 +267,8 @@
             while (index < checks.length) {
                 if (checks[index].equals("unsupported")) {
                     return true;
+                } else if (checks[index].equals("requires")) {
+                    index += 2;
                 } else if (checks[index].equals("return")) {
                     index += 2;
                 } else if (checks[index].startsWith("check")) {
@@ -280,7 +286,34 @@
         }
         return false;
     }
-
+    
+    String isRequiresFunc(CFunc cfunc) {
+        String[] checks = mChecker.getChecks(cfunc.getName());
+        int index = 1;
+        if (checks != null) {
+            while (index < checks.length) {
+                if (checks[index].equals("unsupported")) {
+                    index += 1;
+                } else if (checks[index].equals("requires")) {
+                    return checks[index+1];
+                } else if (checks[index].equals("return")) {
+                    index += 2;
+                } else if (checks[index].startsWith("check")) {
+                    index += 3;
+                } else if (checks[index].equals("ifcheck")) {
+                    index += 5;
+                } else if (checks[index].equals("nullAllowed")) {
+                    index += 1;
+                } else {
+                    System.out.println("Error: unknown keyword \"" +
+                                       checks[index] + "\"");
+                    System.exit(0);
+                }
+            }
+        }
+        return null;
+    }
+    
     void emitNativeBoundsChecks(CFunc cfunc, String cname, PrintStream out,
             boolean isBuffer, boolean emitExceptionCheck, String offset, String remaining, String iii) {
 
@@ -365,6 +398,9 @@
                         } else if (checks[index].equals("unsupported")) {
                             // ignore
                             index += 1;
+                        } else if (checks[index].equals("requires")) {
+                            // ignore
+                            index += 2;
                         } else if (checks[index].equals("nullAllowed")) {
                             // ignore
                             index += 1;
@@ -776,7 +812,23 @@
             out.println();
             return;
         }
-
+        
+        String requiresExtension = isRequiresFunc(cfunc);
+        if (requiresExtension != null) {
+            out.println(indent +
+                        "if (! supportsExtension(_env, _this, have_" + requiresExtension + "ID)) {");
+            out.println(indent + indent +
+                        "_env->ThrowNew(UOEClass,");
+            out.println(indent + indent +
+                        "    \"" + cfunc.getName() + "\");");
+            if (isVoid) {
+                out.println(indent + indent + "    return;");
+            } else {
+                String retval = getErrorReturnValue(cfunc);
+                out.println(indent + indent + "    return " + retval + ";");
+            }
+            out.println(indent + "}");
+        }
         if (mUseContextPointer) {
             out.println(indent +
                 "android::gl::ogles_context_t *ctx = getContext(_env, _this);");
diff --git a/opengl/tools/glgen/stubs/jsr239/GLCHeader.cpp b/opengl/tools/glgen/stubs/jsr239/GLCHeader.cpp
index b3d1c6c..c2464b0 100644
--- a/opengl/tools/glgen/stubs/jsr239/GLCHeader.cpp
+++ b/opengl/tools/glgen/stubs/jsr239/GLCHeader.cpp
@@ -23,6 +23,23 @@
 #include <GLES/gl.h>
 #include <GLES/glext.h>
 
+// Work around differences between the generated name and the actual name.
+
+#define glBlendEquation glBlendEquationOES
+#define glBlendEquationSeparate glBlendEquationSeparateOES
+#define glBlendFuncSeparate glBlendFuncSeparateOES
+#define glGetTexGenfv glGetTexGenfvOES
+#define glGetTexGeniv glGetTexGenivOES
+#define glGetTexGenxv glGetTexGenxvOES
+#define glTexGenf glTexGenfOES
+#define glTexGenfv glTexGenfvOES
+#define glTexGeni glTexGeniOES
+#define glTexGeniv glTexGenivOES
+#define glTexGenx glTexGenxOES
+#define glTexGenxv glTexGenxvOES
+
+
+
 /* special calls implemented in Android's GLES wrapper used to more
  * efficiently bound-check passed arrays */
 extern "C" {
@@ -58,6 +75,11 @@
 static jfieldID positionID;
 static jfieldID limitID;
 static jfieldID elementSizeShiftID;
+static jfieldID haveCheckedExtensionsID;
+static jfieldID have_OES_blend_equation_separateID;
+static jfieldID have_OES_blend_subtractID;
+static jfieldID have_OES_framebuffer_objectID;
+static jfieldID have_OES_texture_cube_mapID;
 
 /* Cache method IDs each time the class is loaded. */
 
@@ -72,6 +94,11 @@
 
     jclass g11impClassLocal = _env->FindClass("com/google/android/gles_jni/GLImpl");
     G11ImplClass = (jclass) _env->NewGlobalRef(g11impClassLocal);
+    haveCheckedExtensionsID =  _env->GetFieldID(G11ImplClass, "haveCheckedExtensions", "Z");
+    have_OES_blend_equation_separateID =  _env->GetFieldID(G11ImplClass, "have_OES_blend_equation_separate", "Z");
+    have_OES_blend_subtractID =  _env->GetFieldID(G11ImplClass, "have_OES_blend_subtract", "Z");
+    have_OES_framebuffer_objectID =  _env->GetFieldID(G11ImplClass, "have_OES_framebuffer_object", "Z");
+    have_OES_texture_cube_mapID =  _env->GetFieldID(G11ImplClass, "have_OES_texture_cube_map", "Z");
 
     getBasePointerID = _env->GetStaticMethodID(nioAccessClass,
             "getBasePointer", "(Ljava/nio/Buffer;)J");
@@ -193,5 +220,63 @@
     return numCompressedTextureFormats;
 }
 
+// Check if the extension at the head of pExtensions is pExtension. Note that pExtensions is
+// terminated by either 0 or space, while pExtension is terminated by 0.
+
+static bool
+extensionEqual(const GLubyte* pExtensions, const GLubyte* pExtension) {
+    while (true) {
+        char a = *pExtensions++;
+        char b = *pExtension++;
+        bool aEnd = a == '\0' || a == ' ';
+        bool bEnd = b == '\0';
+        if ( aEnd || bEnd) {
+            return aEnd == bEnd;
+        }
+        if ( a != b ) {
+            return false;
+        }
+    }
+}
+
+static const GLubyte*
+nextExtension(const GLubyte* pExtensions) {
+    while (true) {
+        char a = *pExtensions++;
+        if ( a == '\0') {
+            return pExtensions-1;
+        } else if ( a == ' ') {
+            return pExtensions;
+        }
+    }
+}
+    
+static bool
+checkForExtension(const GLubyte* pExtensions, const GLubyte* pExtension) {
+    for (;*pExtensions != '\0'; pExtensions = nextExtension(pExtensions)) {
+        if (extensionEqual(pExtensions, pExtension)) {
+            return true;
+        }
+    }
+    return false;
+}
+
+static bool
+supportsExtension(JNIEnv *_env, jobject impl, jfieldID fieldId) {
+    if (!_env->GetBooleanField(impl, haveCheckedExtensionsID)) {
+        _env->SetBooleanField(impl, haveCheckedExtensionsID, true);
+        const GLubyte* sExtensions = glGetString(GL_EXTENSIONS);
+        _env->SetBooleanField(impl, have_OES_blend_equation_separateID,
+            checkForExtension(sExtensions, (const GLubyte*) "GL_OES_blend_equation_separate"));
+        _env->SetBooleanField(impl, have_OES_blend_subtractID,
+            checkForExtension(sExtensions, (const GLubyte*) "GL_OES_blend_subtract"));
+        _env->SetBooleanField(impl, have_OES_framebuffer_objectID,
+            checkForExtension(sExtensions, (const GLubyte*) "GL_OES_framebuffer_object"));
+        _env->SetBooleanField(impl, have_OES_texture_cube_mapID,
+            checkForExtension(sExtensions, (const GLubyte*) "GL_OES_texture_cube_map"));
+    }
+    return _env->GetBooleanField(impl, fieldId);
+}
+
 // --------------------------------------------------------------------------
 
diff --git a/opengl/tools/glgen/stubs/jsr239/GLImplHeader.java-impl b/opengl/tools/glgen/stubs/jsr239/GLImplHeader.java-impl
index 76fea3f..3727106 100644
--- a/opengl/tools/glgen/stubs/jsr239/GLImplHeader.java-impl
+++ b/opengl/tools/glgen/stubs/jsr239/GLImplHeader.java-impl
@@ -47,6 +47,12 @@
     Buffer _pointSizePointerOES = null;
     Buffer _matrixIndexPointerOES = null;
     Buffer _weightPointerOES = null;
+    
+    private boolean haveCheckedExtensions;
+    private boolean have_OES_blend_equation_separate;
+    private boolean have_OES_blend_subtract;
+    private boolean have_OES_framebuffer_object;
+    private boolean have_OES_texture_cube_map;
 
     public GLImpl() {
     }