After reading several discussions here that said you can't get the SMS number from overseas, I ran across this on Kottke.org:

To call a U. S. or Canadian toll-free number from France:

- instead of 800, dial 00 1 880
- instead of 877, dial 00 1 882
- instead of 888, dial 00 1 881

and then the last seven digits of the number you are calling. So, if you are trying to call 800-555-1212, dial 00 1 880 555 1212 instead. This call will be charged at the regular rate of a phone call to the US or Canada (i.e. it's not toll-free). C'est simple

Anyone know if this works?