GL_FIXED documentation

I can’t find the documentation for GL_FIXED (as used in http://www.opengl.org/wiki/GLAPI/glVertexAttribPointer)?

Looks like it was added in GL 4.2 core for compatibility with OpenGL ES 2 (though… I don’t think GL_FIXED has been a fast path since the original OpenGL ES 1.x devices).

Here’s the original spec, from OpenGL ES:http://www.opengl.org/registry/specs/OES/OES_fixed_point.txt

And here it is as an ARB extension:
http://www.opengl.org/registry/specs/ARB/ES2_compatibility.txt