Textures on Bézier Patches (evaluators)

Hello,

I have some Bézier patches which compose a circus. As I want to give it color bands I use a one-dimensional texture of 2 texels, one color each; the MIN an MAG filters are both set to GL_NEAREST.

When I test the scene using an ATI card everything gos fine (http://etanol.is.dreaming.org/circus1.png). But when I try on nVidia it only renders one color (the first texel specified, http://etanol.is.dreaming.org/circus2.png)..)

The toolkits I use (apart from GL) are GLU and GLUT. Am I doing something wrong or is a driver/support problem?

Thanks in advance.

P.S: If you want to see code please ask for it. I can upload it to the address mentioned above.