I guess you are hitting the caveat CSCsd97829 on the 12.4 platforms. This seems an open caveat and will probably fixed in the next release of the IOS. I dont think there is any workaround for this problem. Best thing to do is not to enable SSL VPN on this router. Have a look at the release notes:
Login to the FXOS chassis manager.
Direct your browser to https://hostname/, and log-in using the user-name and password.
Go to Help > About and check the current version:
Check the current version availa...
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...