freezes when switching to VTs (kernel 2.6.5)

[ale]

I'm experimenting system freezes when I switch to VTs.
It always occours this way:

Start the system in X -->OK
switch to VT -->OK
switch to X again -->OK
switch to VT again --> FREEZE <--

System hangs up only with the 2.6.5 kernel I've just installed. It doesn't occour with 2.4.24 kernel .
I've searched the forum but I haven't find anything related.
Any hint?

Ale.

P.D. Kernel and drivers compiled with GCC-2.95.3

My system
-----------

XFree-4.0.3.1
NVIDIA driver: 5336
card: FX5200
memory: 640MB
processor: amd Athlon Xp 1700+
Motherboard: KT133A
Everything compiled from source

[ale]

I've realized it's not NVIDIA driver fault.
I got the same results using NV XFree driver.