We have one of the concurrent program which developed in XML and it has been used for printing checks in one of the location where we operates. This issue occure only in condition when we have combination of following setup :
1. Portal 3.0.9 login server (iAS 18.104.22.168.2).
2. Siteminder as authentication software.
4. Concurrent Managers are running on Virtual Host.
The only solution which I found to overcome this situation to move our Concurrent Manger from Virtual Host to Physical Host. Other than that we do not have any other problem in using Virtual host.
Happy Troubleshooting !!!