Sometimes increasing the LogLevel of the cupsd scheduler can help you find out what's going on. You can do this with:
# mkdir -p /etc/e-smith/templates-custom/etc/cups/cupsd.conf
# cp /etc/e-smith/templates{,-custom}/etc/cups/cupsd.conf/20LogLevel
# sed -i s/info$/debug/ /etc/e-smith/templates-custom/etc/cups/cupsd.conf/20LogLevel
# signal-event cups-reconfigure
Feel free to e-mail me if you want me to have a look at the logs. My e-mail address is in the documentation for e-smith-cups.
Cheers,
Robert