I've observed, that authentication failure, while connecting with jboss-client implementation of JMX remoting (remote+http) causes a thread leak.

Please find the attached code snippet to reproduce the faulty behavior.

The attached code produces following output in my case :

Thread count before starting: 2
Active threads AFTER start: 2
Connection failed.
Active threads AFTER after success: 7
Connection failed.
Active threads AFTER after failure: 12

Possible cause.
After an initial analisys I've observed that RemotingConnector.internalConnect throws an Exception, while having state set to UNUSED, while I'd actually expect it being set to OPEN, as connection and endpoint fields are already initialized.