When trying to connect to openfire from Gajim (one of the most popular UNIX clients) Gajim says that there was something with my user/password and Openfire claims in warn log that:
2013.02.27 11:31:34 org.jivesoftware.openfire.net.StanzaHandler - Unexpected packet tag (not message,iq,presence)
Thanks, so it is likely OF-509 and OF-636 to blame here. The ‘simpliest’ solution is to switch to Oracle JVM and not use icedtea until these bugs are fixed.