Yes an ADSL2+ Modem for the new ALIX APU would be a very very cool thing for all the users of pfsense, ipfire and all the other firewall / router distributions out there. Please think about integrating ADSL2+ modems to your hardware cause your hardware is great! That would realy be the cherry on the cake!
This so much. Sadly the range of choices is abysmal to none.
The guys at https://omnia.turris.cz/en are also aware of the acute demand in EU/Asia and are in a position to make an ADSL modem. They even tried some stuff from China and weren't happy with it's VDSL performance. So they can't profitably make one (they only thing they're lacking is larger pre-order numbers for the good a/v dsl chipset manufacturers) it is highly unlikely that Pascal would be able to offer this in spite of being an almost 0 competition market right now. The best suggestions they received was to interface it via ethernet/SFP.