Hi all,

I've set up a JBoss AS 5.1 installation of Guvnor (5.3.1 GA) using the JBPM 5.2 installer (installed using the provided ANT script).

After some usage of Guvnor and jbpm-console without apparent issues, jbpm-console becomes unable to communicate with Guvnor.

Snippet of "server.log":

2012-07-11 12:22:47,803 ERROR [STDERR] (http-0.0.0.0-8080-1) java.lang.LinkageError: loader constraint violation: when resolving overridden method "com.sun.xml.bind.v2.runti
me.MarshallerImpl.marshal(Ljava/lang/Object;Ljavax/xml/stream/XMLStreamWriter;)V" the class loader (instance of org/jboss/classloader/spi/base/BaseClassLoader) of the curren
t class, com/sun/xml/bind/v2/runtime/MarshallerImpl, and its superclass loader (instance of <bootloader>), have different Class objects for the type javax/xml/stream/XMLStre
amWriter used in the signature
2012-07-11 12:22:47,809 ERROR [STDERR] (http-0.0.0.0-8080-1)    at com.sun.xml.bind.v2.runtime.JAXBContextImpl.createMarshaller(JAXBContextImpl.java:772)
2012-07-11 12:22:47,809 ERROR [STDERR] (http-0.0.0.0-8080-1)    at com.sun.xml.bind.v2.runtime.JAXBContextImpl.createMarshaller(JAXBContextImpl.java:141)
...
012-07-11 12:22:47,825 INFO  [STDOUT] (http-0.0.0.0-8080-7) 12:22:47,825 ERROR [GuvnorConnectionUtils] Error retriving packages from guvnor: ParseError at [row,col]:[2,1]
Message: XML document structures must start and end within the same entity.
2012-07-11 12:22:47,847 INFO  [STDOUT] (http-0.0.0.0-8080-7) 12:22:47,847 INFO  [GuvnorConnectionUtils] Did not find process image for: com.sample.evaluation
2012-07-11 12:22:47,847 INFO  [STDOUT] (http-0.0.0.0-8080-7) 12:22:47,847 ERROR [GraphViewerPluginImpl] Could not get diagram url from Guvnor: null

Now, since jaxb is part of the JRE since version 1.6.0_04, I guess some other webapp triggered bootloader classloading of MarshallerImpl.

I removed jaxb-impl-2.2.1.1 from the WEB-INF/lib folder of drools-guvnor and now it appears to run without problems.

Wouldn't it be better to remove jaxb-impl from WEB-INF/lib in guvnor distribution wars? Do I miss something?

Thanks in advance, regards.

Marco