On Friday, I discovered a way to unlock Packet8‘s DTA-310 terminal adapters. Strom Carlson did some sleuthing and discovered the device Packet8 uses is the same as Sip-In-One’s. He flashed the DTA-310 wit a Sip-In-One firmware image and it worked. Thus, if you cancelled your Packet8 service and have no use for your TA, you can now flash it and use it with Asterisk.
I’ve added a link to Strom’s page on my Asterisk webpage.