GUI Interface ASA 5510 setup
From DocWiki
IPv6 for https server works almost exactly the same as IPv4, notice that you can do a /64 instead of a bit mask
example:
ASA(config)# http fc00:0:0:7326::1/64 inside0
ASA(config)# http server enable
ASA(config)# asdm image disk0:asdm-625.bin (depending on your asdm image)