A number of folks reported issues when running the jBPM BPEL 1.1-beta1 examples in JDK 1.5. The easiest solution is using the endorsed standards override mechanism as described in the jBPM BPEL user guide.
If you cannot or do not want to use the above mechanism, follow these steps:
Set the system property com.sun.xml.namespace.QName.useCompatibleSerialVersionUID to value 1.0 before you start the Ant build. From the command line, set the ANT_OPTS environment property to -Dcom.sun.xml.namespace.QName.useCompatibleSerialVersionUID=1.0 so that the ant batch file/shell script passes the system property to the JVM.
Replace BPEL_HOME/doc/examples/process.template.xml with the attached file.
The first step is necessary due to an issue with the serialVersionUID of class javax.xml.namespace.QName fixed in JDK 1.5.0_07. Older builds of JDK 1.5 might not require it. See the related forum topic for details.