My new telecom provider is going to charge us a fortune to have our DNIS digits as anything other than the last four digits of the toll-free number they are assigned to. (ie 800-999-9999 has DNIS 1501 not 9999) The problem is that our toll-free numbers are not unique in that format and are only unique at 10 digits.

My PBX vendor is saying we can only route 7 DNIS digits because the system only allows 7 digit extensions, speed dials, etc.... It doesn't make sense to me that the PBX can accept 10 digits but we can't route on them...Any advice?? I played with ARS etc with no luck....

Our system is a Mitel 3300 ICP....