use glBlendFuncSeparate with CCSprite

Hi,

is there any way that i can use glBlendFuncSeparate with CCSprite? I know i can set the blending with CCSprite::setBlendFunc(ccBlendFunc), but that maps to glBlendFunc, not glBlendFuncSeparate.
By now i’ve just created a CCSprite subclass with the draw method reimplemented (changing the glBlendFunc with glBlendFuncSeparate).

Is ccBlendFunc part of cocos2d? Is there any chance that we can extend it to include the other 2 params that glBlendFuncSeparate uses?