Last year Nortel signed up Advatel from Australia as a development partner. The fruits of the partnership look like they are paying off for the sipXecs / Nortel SCS500 customers.
Advatel's PhoneEasy IP Console and PhoneEasy IP Desktop are now orderable items through Nortel for use with the SCS500. Press Release
Additionally, earlier this year Advatel had signed up Telesource Services, LLC as a distribution partner in the US for the PhoneEasy line of products. Press Release