AVAYA does not have a real PCBX yet. There approach like Dana says is similair. The IP600 is proberbly the product that fits the profile. Most of the technical specs are only availible from the web if you are a business partner
Intel is something you’re may be interesseted in aswell:
Intel converged communication platform
ftp://download.intel.com/apac/eng/network/ICCP_over.pdf
regards,
Cliff