palleted textures

Hello guys,
I am trying to combine (alpha blending) 3 textures one of them is a color index texture (palleted texture) the two others are regular RGBA. Input from the keyboard triggers a change in the pallete through the function call ‘glColorTableEXT’. When doing so I see a strange phenomena:I see changes in the palleted texture only when it is the last one to combine (3rd one). If it is the first or second one - NO changes occures (I checked - ‘glColorTableEXT’ is always called).
Is it OpenGL limitation? Bug in the driver?
Thanks,
Yossi