Upgrade to 6.3(3) and move the specific syslog messages you want to send to your SNMP server to level 0 (logging message syslog_id [level level]). Then set the logging history command send level 0 commands to your SNMP server. Give it a go and see if that works for ya.
We have configured the outside and inside Interface with official ipv6 adresses, set a default route on outside Interface to our router, we also have definied a rule , which also gets hits, to permit tcp from inside Interface to any6.
In Syslog I also se...