gtkglarea, vista, poor fps

Hi all,

I develop an opengl application using gtk 2.4 and gtkglarea 1.99.
After some testing on windows vista and seven platfrom, it appears that =

the framerate of my opengl widget is divided by two in comparison with =

windows xp.
Has everybody ever encountered same kind of issue ?
Will it be solved if I upgrade to gtkglarea 2.0.1 ?

Thanks for helping.
Beno=EEt.