The syslog errors look very bad.
Ill attach my config which is working fine so far. It only ignores the users "voicemail" settings and starts the voicemail always if the user isnt connected or doesnt pick up the phone within the timeout.
Just adapt it to your system and it should work.
Both SER's, the SEM and the mysql db are on the same server in this example.
best regards,
Arnd