Can I have two UIE persistence record for the same connection

I have a web service that uses the ASP.NET_SessionID cookie for persistence.  However, I'm running into scenarios where the ASP.NET_SessionID is not sent in the request, or the value of that cookie is blank.  This of course is breaking persistence.  I'm trying to get the developers to fix that issue, but they're not having a lot of luck.

Normally it would make sense to set Source_Addr as the fallback persistence method, but in this case the traffic is going through a third party, which changes the client IP address.  The original client IP address is included in a X-Forwarded-For header.

My question is this:  In my iRule, can I create a UIE persistence record for the ASP.NET_SessionID cookie and also a UIE record for the X-Forwarded-For value, or will they overwrite one another? 

If I can't do that, can I create a source_addr persistence record using the value in the X-Forwarded-For header?

Thanks for any help on this.

Robert