I would like to have the ability to mark a call as spam. This feature is now available on the new firmware for 88XX SIP phones (version 12.7(1) ) and it would great to have that feature parity with Jabber.
Here is the info from the release notes for reference:
Mark A Call as SpamYou can use the Mark spam feature to reduce the number of unwanted calls you receive. With this feature,you designate a phone number as either a fraudulent call or as a telemarketer call. Fraudulent calls are declinedand blocked. Telemarketer calls ring through to you. But these calls have the term Telemarketer in the IncomingCall Alert and they have an icon next to them in Recents.You mark active, or recent calls. You can view and edit your Spam call list from the Settings menu. TheSpam call list can have up to 150 calls.