In the main Enterprise Vault Documentation details are given on how to setup ISA and Enterprise Vault together, but as of yet, I’ve not seen the same information for Microsoft Threat Management Gateway 2010. One of the Support Engineers has put together the following technote, which I’ve not had time to try out yet. Have a go, and see if there are additional steps which are needed? I’d be happy to send the engineer any feedback that arises.
Here is a link to the article : http://www.symantec.com/business/support//index?page=content&id=HOWTO59068