As I noticed some constants like GL_CONSTANT_COLOR, GL_ONE_MINUS_CONSTANT_COLOR, GL_CONSTANT_ALPHA, and GL_ONE_MINUS_CONSTANT_ALPHA are not available for OpenGL ES 1.0
http://www.khronos.org/opengles/sdk/1.1/docs/man/ http://www.khronos.org/opengles/sdk/1.1/docs/man/glBlendFunc.xml http://www.khronos.org/registry/gles/specs/1.1/es_full_spec_1.1.12.pdf there is no such constant in ES1.