The code that now makes up the sipXecs sipXcom project was first contributed to SIPfoundry by Pingtel Corp in 2004 as the sipXpbx open source project (Pingtel organized and funded the creation of SIPfoundry, but at the time it is was an independent legal not-for-profit corporation). The PBX code had been under development as the Pingtel SIPxchange product for a couple of years at that point, and was itself an extension of code from the Pingtel Expressa phone before that (the Pingtel Expressa phone was one of the phones that made the very first successful SIP calls between implementations from different vendors). For some time after that initial release, development of the Pingtel commercial product continued in parallel with the sipXpbx open source code base, with contributions continuing from the commercial version to the open source.
In March 0f 2010, Avaya stopped contributing to the source code to the community. Members of the community came together (including several of the original Pingtel employees under the company name eZuce, Inc.) and are now maintaining the projectuntil the beginning of February 2015 maintained the sipXecs project.
Citing differences with SIPfoundry ownership, eZuce decided in February 2015 to fork sipXecs to form sipXcom. eZuce continues to improve and expand the code base.