Type cast error when use gluTessCallback();

[Qiaowen]

Hello.
my code is simple:

static GLUtriangulatorObj *tobj = NULL;
 
gluTessCallback( tobj, GLU_BEGIN, glBegin );
		gluTessCallback( tobj, GLU_VERTEX, glVertex2fv );	
		gluTessCallback( tobj, GLU_END, glEnd );

Then there are two errors,the same type.
error C2664: "gluTessCallback": can not convert parameter 3 from "void (__ stdcall *) (GLenum)" to "void (__ stdcall *) (void)"
What to do to fix it?
Thanks.