X hangs modem/ppp

[Kurt Swigart <kswigart@silverlink.net>]

My ppp connection quits working when I start X.  It doesn't happen all
the time, just about 60%.  Stopping X does not make it better.  The
problem seems to be with the modem (or the serial port), since even if
I kill pppd, I cannot communicate with the modem.  I can't even send it
"ATZ".  I have found no way to "reset" the problem except to reboot.  

I first thought that there may be an IRQ conflict between the mouse
and the modem, but that is not it.  I did not have this problem with
the same hardware but with my old Slackware distribution.  When I
switched to debian, the problem started.  

I have an external Supra 28.8k modem on ttyS3 (irq 3).  My mouse is on
ttyS0 (irq 4).  

Thanks, Kurt

kswigart@silverlink.net