[asterisk-users] Asterisk/Machine Hang after calling in/out ISDN

[Lee, John (Sydney)]

I am testing Asterisk 1.4.22, zaptel 1.4.10.1 and libpri 1.4.4 on RHEL5
on DELL PE2950 and using ISDN-10.
I thought about cutting over to production tonight when I noticed a
serious problem.

SIP calls are fine but if I dialed to outside (Dial(Zap/g1)) a few times
or someone called in a few times, Asterisk just froze (cannot enter
anything on the CLI console) and then even the machine had to be
rebooted.

I suspect there is a problem with zaptel.  
Is zaptel 1.4.10.1 a dodgy verions?
Any suggestion on how to debug this problem?