iNotes 6 error: schedule object doesn't exist

We just upgraded our user’s mail databases to using the iNotes6 template so we can offer web mail.Several employees have encountered a problem when they “accept” a meeting invitation via browser (IE 6) connected to their iNotes maildb → “schedule object doesn’t exist”

We’re running SSL on our Domino Web Mail server.

Our Domino Web Mail server is in a separate domain from our internal corporate Notes Network & is cross-certified.

Has anybody experienced this error and have any suggestions on how to resolve?

Thanks,

kathy d