I have and adtran 908e that we used until now to connect to out PRI T1 port on the phone system
so we have one side the WAN we got in a SIP trunk and on the other side a PRI
now we moved to hosted PBX system
our sonicwall does a very bad job with VoIP SIP NAT i am wondering if we can use the 908e just as router for the VOIP network, how is the NAT with the adtran
you sure can! You can do either Stateful or Transparent proxy. Stateful is where you hosted phones register to the 908e and we proxy them up to the softswitch. Transparent is where the phones register directly to the softswitch. Hope that helps. See the config guide below for how to configure your unit.
Here is the config guide: