Huzzah - thats a start
Having the dialplan used, and number BEFORE and AFTER dialplan would be useful - as I've mentioned before, whilst I've got a dialplan to translate some numbers based on starting with 0 or being a certain number of digits long, to a full international number - which works when dialling from my ATA.
However, when I use mobile.voxalot.com, and provide the full number anyway, which shouldn't be translated, the call fails. If I use the number that I'd dial from my ATA, it works - so obviously a dialplan is kicking in somewhere, and shouldn't be - and it'd be good to find out which one and why!
(I'll play with it later and see if I can spot it anyway)