Hi! I have encountered compile-time error when I try to use tessellator for concave polygon. Anyone know why is this so?

VC++ 6.0 Compile-time Error:
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error C2664: 'gluTessCallback' : cannot convert parameter 3 from 'void (unsigned int)' to 'void (__stdcall *)(void)'
None of the functions with this name in scope match the target type

part of my code:
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glShadeModel(GL_SMOOTH);
glColor3f(0.42f, 0.35f, 0.03f);
GLdouble tess_ver[3];
GLUtesselator* tess;
tess = gluNewTess();

gluTessCallback(tess, GLU_TESS_BEGIN, glBegin);
gluTessCallback(tess, GLU_TESS_VERTEX, glVertex3dv);
gluTessCallback(tess, GLU_TESS_END, glEnd);

gluTessBeginPolygon(tess, NULL);
gluTessBeginContour(tess);
glNormal3f(0.0f, 1.0f, 0.0f);
tess_ver[0] = ...
tess_ver[1] = ...
tess_ver[2] = ...
gluTessVertex(tess, tess_ver, NULL);
gluTessEndContour(tess);
gluEndPolygon(tess);

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The error is on the line gluTessCallback(.....BEGIN....) and gluTessCallback(.....END....)
but not on the line gluTessCallback(....VERTEX....)
Thanks in advance!!!