Random X 4.1.0-6 crashes, lockups on Dell i5000e

[Michael Robinson]

I've recently installed Debian on my Dell i5000e, with the r128 driver
for the ATI Rage Mobility (2.4.9 kernel, 4.1.0-6 X package).  X has been
randomly crashing with a signal 11 (SEGV).  Also, when switching from X to
console mode (CTL-ALT-Fx), the console will occasionally lock up hard,
requiring a system reset.

Are these symptoms that anyone else has encountered, and if so, is there a 
known solution?

Thanks

        -Michael Robinson