[reSIProcate] Registrations with to tag are rejected

[Scott Godin]

I noticed that registrations containing a to tag are discarded by
DialogUsageManager processRequest:

makeResponse(failure, request, 400, "Registration requests can't have To:
tags.");

I know this is to spec, but I have some IPDialog devices that are sending
registration refreshes and unregister requests with a to tag.  Do you think
it would be harmful to just accept these requests, despite the fact that
they are incorrect?

Scott