Glad to hear it! There are a couple of other options that I'll suggest here just for completeness, now that I've thought about it a little longer.
You're using 5.5, which by default does not bind to IPv6 interfaces. You can change that behavior so that 5.5 *does* bind to IPv6 interfaces by including --bind-address=* as a startup option to MySQL Server. I actually just blogged about the change in behavior introduced in 5.6.6 (just released as pre-GA) the other day:
http://mysqlblog.fivefarmers.com/2012/08/13/how-will-ipv6-changes-in-5-6-6-affect-you/
It's entirely possible also that changing "localhost" to "127.0.0.1" (the IPv4 loopback) in your JDBC connection string will also solve the issue without requiring the workaround. I haven't explicitly tested this yet myself (so I could be wrong), as my ancient XP box doesn't have IPv6 enabled right now (and enabling requires a painful reboot).
It's also possible that an entry in the hosts file that links "localhost" with the IPv4 loopback would also work (again, not tested).
Anyhow, glad to hear the problem is solved for you.
Best regards,
--
Todd Farmer
MySQL @ Oracle
http://www.oracle.com/mysql/