Hi Jamie
You'll need to supply more info - typically in the UK we've used Westell iQ boxes as a cheap and reliable method of bridging between DPNSS (as common in the UK on older PBXs) and QSIG as supported by CCM. This may or may not be what you need depending on what connections you have available on your legacy kit.
Unfortunately Westell aren't around (at the moment).
Checkmate (http://www.checkmate.co.uk/) have a solution but it's expensive compared to the Westell boxes.
Regards
Aaron
Aaron
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