problems with gtkglext functions..

[Iker Perez de Albeniz <ialbeniz cbt es>]

Hi,

Iam trying to use vtkmm in my application.. i am building under win32 and
Viscual c++ 2005 Express.. the problem is tha when i compile i have this
errors:

error LNK2019: external symbol _gtk_widget_set_gl_capability unresolved
referred to the function "protected: virtual void __thiscall
RenderingArea::gl_configure(void)"
(?gl_configure RenderingArea@@MAEXXZ)	RenderingArea.obj	

error LNK2019: external symbol _gdk_gl_config_new_by_mode unresolved
referred to the function "protected: virtual void __thiscall
RenderingArea::gl_configure(void)"
(?gl_configure RenderingArea@@MAEXXZ)	RenderingArea.obj	

i dontk know what this errors means?

any idea??
thainks