iPass does a lot of global roaming dialup connections but these days you can often find better alternatives. For example, check where you're going to be staying in france and consider buying a Mobile Broadband service if covered. I think one or two of the operators offer a PAYG deal just like in this country, albeit a bit more expensive (still cheaper than a dial link).
On the other hand if you're going to be in an urban area then there could be a Wi-Fi hotspot nearby, a google search or two might help. BTOpenzone has a lot of international wifi deals.
Mark 'Winter' Jackson
Editor-in-Chief - ISPreview.co.uk