The installer should catch systems where TCP connections cannot be made to localhost

Some systems are not running IPv6 (or have no IPv6 localhost interface configured), however they have
an IPv6 address entry for ::1 listed in the "localhost" record(s) in DNS or /etc/hosts along with the older
IPv4 127.0.0.1 entry. Java prefers IPv6 addresses, and if this case occurs and code won't try all
addresses returned for "localhost", some parts of OpenNMS will break.

Sometimes the address "127.0.0.1" will be used, and this has tended to be the preference to get
around these IPv6-related issues. Sometimes "localhost" will be used, but as users have run into this
problem in different places, it usually gets replaced with "127.0.0.1". It turns out that there are a few
cases where the Java static method InetAddress.getLocalHost() is used, which seems like it can cause
similar issues to using the "localhost" host name on improperly configured hosts. Here's an example:

http://article.gmane.org/gmane.network.opennms.general/15037