I know this doesn't directly address your issue, but I'v found that the best (and cheapest) way to roam in Europe is to take an unlocked GSM phone, and get yourself a pre-paid SIM card when you arrive in Europe. You'll have a local number, and all you'll have to do is provide the number to those you want to be able to reach you (everyone else can wait!)

This works best if you stay put in one country (may need different SIMS in different countries).

Good luck.