Just to clarify, it's a problem with reconnect for outbound message (from jboss to websphere mq) when websphere mq has been restarted, otherwise everything works fine.
The problems seems to be that the connections in the connection pool are not invalidated when connections to websphere mq is lost, so when an outbound message is to be sent it get's a stale connection which fails. Outbound communication starts working again when jboss idleremover has flushed the connection pool.
And it's JBoss 4.2.3.GA (not 4.2.2 as I first wrote), and Websphere MQ 6.2.0.5.
Any help would be appreciated.