I myself got a SPA-941. I think this is the correct setup for voxalot.
Proxy and registration:
proxy: voxalot.com
Subscriber information:
Displayname: <your voxalot number>
User ID:<your voxalot number>
Auth ID:<your voxalot number>
Password:[your password]
Call Feature Settings:
Message waiting: no
Voice mail server: <your voxalot number>@voxalot.com
Dial plan:
Dial plan: L:20,S:7,( x | *xx | 911S0 | 1[2-9]xx[2-9]xxxxxxS0 <:@sipbroker.com> | [x*][x*]. <:@sipbroker.com> | <#:>[x*][x*]. )
Enable IP dialing: yes
Screenshot:
P.S: Maybe topic can be changed in: "Settings I use for voxalot.com"