INVALID_ENUM on glTexImage2DMultisample

Hello everyone,
i’m trying to create a multisampled FBO but i get a GL_INVALID_ENUM on
glTexImage2DMultisample(GL_TEXTURE_2D_MULTISAMPLE,2,GL_RGBA,1024,768,false);

I can’t understand this error since it’s not even described in the wiki: only INVALID_OPERATION and INVALID_VALUE should be thrown as possible errors.

Any hint?
Thanks