3com has two product lines. The nbx and the vcx. The vcx is sip native and the nbx can be upgraded. (they also rebrand digium's asterisk appliance)
They continue to release hardware based on the nbx line. From what I have read they have no plans on discontinuing the nbx line. While sip is nice, it is not the end all best protocol for voip. Also, not every install needs to be sip.