I have a weird issue I've never seen before. First off, I am not a phone system guy. I have worked on some LG Ericson and Vodavi systems, but by no means am I an expert. I will not be performing any suggestions about my problem, but passing them on to a more qualified person. Having said that, I am an intercom guy and deal with Rauland, Valcom, Dukane and Bogen systems on a daily basis. Anyways, here's the problem.
Not too long ago, phone systems started getting upgraded around here (school system). Normally, to access the paging system, the user would hit "page" and would get the dial tone from the intercom, and dial #01* for instance, to make a zone page. Now, after these upgrades, they get the dial tone but it seems its not getting the #. Sometimes, after waiting 5 seconds or so it will work fine. Sometimes dialing ##01* will work. I can connect my butt-set directly to the paging system all day long with no issues, and since its only an issue with schools that have upgraded their phone systems all clues point that direction.

Any clues?
Intercoms being affected are Rauland Telecenter ICS and Telecenter V

The phone system is a Nortel Mg1000, I think.