[Asterisk-Users] Unable to create channel of type 'Zap'

[Mona Meyer]

I installed Asterisk 1.0 CVS on a Debian Sarge System. I am using two
ISDN-HFC-Cards and a point-to-point ISDN Connection.

Everything seemed to work pefectly. But today I realized that I cannot
use two lines at the same time. I get the error message:

3 active channel(s)
asterisk*CLI> show channels
        Channel  (Context    Extension    Pri )   State Appl.        
Data
        Zap/2-1  (internS0   555858       2   )    Ring (None)       
(None)
 SIP/user1-e4eb  (from-sip                1   )      Up Bridged Call 
Zap/4-1
        Zap/4-1  (externS0   4445858     1   )      Up Dial         
SIP/user1|20|t

Sep 27 15:13:56 NOTICE[13491]: app_dial.c:805 dial_exec: Unable to
create channel of type 'Zap'

I restarted Asterisk and it worked for 1 or 2 times. After that I had
the same problem.

Any hints, where I can start searching? Is there any possiblity to
force the channel to "hangup" or something like that?