Every once in a while our openfire instance will drop all connections and not accept new ones - the server will accept tcp connections but there is no reply when testing some XMPP with telnet or netcat. Additionally, when using the admin panel web interface the Session page will not load, it just hangs indefinitely. We are using LDAP auth but the LDAP server does not seem to be the problem since I can log in to the web interface and other services can still access ldap.
There is nothing in the log that indicates a problem (debug logging is enabled now). I am at my wits end with this, I don't know how to debug the problem further and I'm unable to somehow trigger the problem. I have attached jstack output of a hung process.