I spoted it in version 4.1.1 I'm not sure if call it a bug but: When amq library connets to amq server. The name of the connection gets an id. It is in pattern of ID + computer_name + some string When the computer has non standart characters like ą ł ę in the name (windows computer name, I did not test it on Linux) the queue recives the report and after whole activemq is blocked. LocalTransaction - POST COMMIT FAILED: java.lang.RuntimeException: java.io.IOException: Failed to broker message: "id of the broker" in container: java.io.UTFDataFormatException: bad string -- View this message in context: http://www.nabble.com/Non-standart-characters-in-computer-name-block-activemq-tf4592447s2354.html#a13110343 Sent from the ActiveMQ - User mailing list archive at Nabble.com.