Jimbobebob

I don't know if this is considered a MARP question or not...

We've recently installed an Option 61C (25.40B) to replace an old SL-1 NT ('Opt 21' brains). Now users are reporting that when they place internal calls from a DN that appears on multiple sets, the called party sees the name/DN of the extension making the call, a colon, and the name/DN of the phone from which the MARP DN call was made (i.e., if my extension is x223 'Jimbob', but I call from my line appearance on my co-worker's phone x224 'Fred', the person I call internally will show
'Jimbob:Fred' ). I think it's kind of a neat feature....that way they can see that you're not actually making that call from your own phone, but from your line appearance on someone else's phone.
The customer would like to turn that feature off, but I don't know which software option turned it on in the first place! Is is a CLS feature of the phones themselves (LD 10/11) or is it a global option (LD 15 CDB)??

Thanks for the help,
Jim