Hi,
Thank you for your reply. I was lucky to get it work last night.
I am using - SOA-P-5.1 + JBDS 4.0 on Window Platform
I did 2 things
1) Changed the Server Deployer from "/jbpm-console/upload" to "/gpd-deployer/upload"
2) Changed <attribute name="DownloadServerClasses">true</attribute> (from false to true)
in jboss-soa-p-5\jboss-as\server\default\conf\jboss-service.xml
[The usage of this attribute is written on SOA Getting Started Guide Section 2.4.5]
I figured the 2nd step after I read https://issues.jboss.org/browse/SOA-1586 mentioned about 'secured' and 'unsecured' profile
Hope this may help others.