according to http://java.sun.com/j2ee/1.4/docs/api/javax/resource/spi/work/ExecutionContext.html the transaction timeout (used by WorkWrapper/JBossWorkManager) is given in SECONDS, JBoss interprets this value as MILLISECONDS, hence we get a thread terminated after 60 msecs which are meant to be 60 seconds by the resource adapter.
I dont know if anyone had this problem before, just want to let know about this. We will patch JBoss (4.0.3sp1) ourselfes, because with JBoss you never know if a bug will be fixed or even if you get a reply in the support forum at all.
