I found out that in the current distribution of Xastir in UBUNTU (Xastir 1.9.2) the iGating sometimes stopps. The modem connections (to a Kiss modem on the one and TCP/IP on the other hand are still working, but no traffic modem -> tcp/ip or vice versa takes place...
System and Equipment used:
TinyTrack Alpha 0.52 KISS MODE @ icom ic 2350H
Siemens Primergy Server 2 x 1 GHz, 1 GB RAM, UBUNTU 8.10
best regards / vy73
Chris Cramer, DF5KX