New install - items stuck in send queue

I just rebuilt a Hylafax+IAXmodem+FreePBX setup after many years of working great.  Hylafax worked so well that I haven't touched the config for many years...and so my problem


I reinstalled Hylafax from an RPM (CentOS), and IAXmodem from source.  Both appear to be installed and working...but when I send a fax it just waits in the send queue:


[root@pbx1 hylafax]# faxstat -s
HylaFAX scheduler on pbx1.mydomain.ca: Running
Modem ttyIAX1 (+1.619.266.4357): Running and idle
Modem ttyIAX0 (+1.216.848.7506): Running and idle

JID  Pri S  Owner Number       Pages Dials     TTS Status
2    128 B faxuse 6192728238    0:0   0:3          Blocked by concurrent cal
1    128 W faxuse 6192728238    0:0   0:3

I assume the W means waiting...but why?  Why won't hylafax use the modem and send the fax?


?