HylaFAX is an enterprise-class system for sending and receiving facsimiles as well as for sending alpha-numeric pages.
On Debian you can easily setup an Hylafax Server installing it by:
aptitude install hylafax
And configure your fax device with faxaddmodem:
At this point, the faxserver was correctly receiving faxes but the sending was constatly failing due to no carrier errors:
Nov 16 12:18:09 hylafax FaxSend: SEND FAILED: JOB N DEST XXXXXXX ERR  No carrier detected
You should add to /etc/hylafax/config.ttyACM0 for fixing the problem: