I tried Andrija Petrovic's patch for smsc_at posted Sept.11 ( http://www.kannel.org/pipermail/devel/2007-September/001212.html). And it seems to work! Before that I was getting 'generic error' on send SMS all the time, and none of the retries ever worked. Now the retries seem to work.
This is with a multimodem EDGE USB modem. Thanks Andrija! Julian Paas Liketribe
