URGENT - Domino 6.5 with IHS - session-based authentication problem

Hello!We have the following problem that because of the project commitments needs to be resolved as soon as possible:

We have configured Domino 6.5 with IHS 1.3.26 and WAS 5 plugin on a separate box. Everything works (including basic authentication) with exception of session-based authentication. While having this option enabled in Domino, we get an Internet Explorer error that page cannot be displayed.

The plugin-cfg.xml has been modified as specified in the Domino 6.5 Admin Help and I can provide addtional configuration details if necessary.

I’d appreciate any suggestions as to how this might be resolved.

Thanks in advance.

Voi