Do VIPs support multiple certificates? Told my sysadmin no.

Recently moved some mail servers off TMG to behind f5. We are part of a consortium so different businesses are allowed to email each other. Just got this IM from a sysadmin:

"I've just realized that our free/busy woes are due to the F5 not having the "federation" SSL certificate in the mix during the SSL bridging (termination and re-encryption (client and server profiles))."

Is there a fix for something like this?

Thanks,

Mike