We're entirely a sccp shop, no sip phones here. However, we're looking a disaster recovery site that can tie into our voice network and allow our phones to register just as they do now, I've tested this and it works just fine. However, they have Linksys phones that are running SIP that they say we can use in the event we don't have our own phones readily available. Is there anything special I need to do with our UCM's to ensure a SIP phone can register with it? Does it use the same license units?