用vc.net编译一个工程，里面调用了很多opengl的函数，编译报错提示:

d:\program files\microsoft visual studio 8\vc\include\gl\gl.h(44) : warning C4005: 'APIENTRY' : macro redefinition
d:\program files\microsoft visual studio 8\vc\platformsdk\include\windef.h(125) : see previous definition of 'APIENTRY'
Generating Code...
Compiling manifest to resources...
Linking...
HUD_tbi.obj : error LNK2001: unresolved external symbol _glPopMatrix
splash.obj : error LNK2001: unresolved external symbol _glPopMatrix
panelnode.obj : error LNK2001: unresolved external symbol _glPopMatrix
wxradar.obj : error LNK2001: unresolved external symbol _glPopMatrix
HUD.obj : error LNK2001: unresolved external symbol _glPopMatrix
HUD_ladder.obj : error LNK2001: unresolved external symbol _glPopMatrix
HUD_runway.obj : error LNK2001: unresolved external symbol _glPopMatrix
hud_rwy.obj : error LNK2001: unresolved external symbol _glPopMatrix
hud_tbi.obj : error LNK2001: unresolved external symbol _glPopMatrix
panel.obj : error LNK2001: unresolved external symbol _glPopMatrix
od_gauge.obj : error LNK2001: unresolved external symbol _glPopMatrix
ATCdisplay.obj : error LNK2019: unresolved external symbol _glPopMatrix referenced in function "public: virtual void __thiscall FGATCDisplay::update(double)" (?update@FGATCDisplay@@UAEXN@Z)
hud.obj : error LNK2001: unresolved external symbol _glPopMatrix
hud_labl.obj : error LNK2001: unresolved external symbol _glPopMatrix
hud_ladr.obj : error LNK2001: unresolved external symbol _glPopMatrix
HUD_runway.obj : error LNK2001: unresolved external symbol _glEnable
renderer.obj : error LNK2001: unresolved external symbol _glEnable
splash.obj : error LNK2001: unresolved external symbol _glEnable

说明下，我已经连接了opengl32.lib glut32.lib.glaux.lib库文件，并且包含了gl中的头文件。
请问这是什么原因哦？谢谢