Hi Simon,
So the AnyConnect is supported as long as the router is using a version higher than 12.4(20)T or later. This link is going to respond all your questions:
http://www.cisco.com/c/en/us/support/docs/security/anyconnect-secure-mobility-client/200533-AnyConnect-Configure-Basic-SSLVPN-for-I.html
and you can also use this link for CCP configuration:
http://www.cisco.com/c/en/us/support/docs/routers/3800-series-integrated-services-routers/110608-ssl-ios-00.html#anc2
Hope this info helps!!
Rate if helps you!!
-JP-