warning i'm getting

[Fairleigh]

WARNING[4216] pbx.c: Channel 'SIP/SIPtrunk-086622f0' sent into invalid extension '850266666666666701' in context 'default', but no invalid handler

what would cause this, when this happens from what i can tell no agents can login and all dialing stops...

Thanks
for any info u can supply

[mflorell]

Asterisk version?
astguiclient version?

that exten is for sending to a specific voicemail box.