Using bytecode enhancement at build time and the -Dopenjpa.DynamicEnhancementAgent=false
switch at runtime solved the problem without the need to change the JAR's manifest or something else. Thanks to all Tobias -- View this message in context: http://openjpa.208410.n2.nabble.com/Error-com-ibm-tools-attach-AttachNotSupportedException-tp5989284p6629665.html Sent from the OpenJPA Users mailing list archive at Nabble.com.