title: glTexImage2DMultisample gives error with SNORM internal formats
body: <p>glTexImage2DMultisample gives GL_INVALID_ENUM error when called with snorm internal formats. when i checked <a href="http://www.opengl.org/sdk/docs/man3/xhtml/glTexImage2DMultisample.xml" rel="nofollow">http://www.opengl.org/sdk/docs/man3/xhtml/glTexImage2DMultisample.xml</a> , and it does not specifies any operation with error GL_INVALID_ENUM. 
  Is snorm formats are supported for that API or not?</p>