According to this official list from Apple all the carriers in France sell phones that are locked to the carrier. I bought my iPhone 4 in an Apple store in Canada, officially unlocked and usable with any SIM around the world.

http://support.apple.com/kb/HT1937


You may need this link to access the data profile of the specific carrier that you use. You may need to update the APN profile. This can all be done without jailbreaking your new phone.

http://www.iphoneuserguide.com/apple...for-iphone-3g/

Or you can download the app from this site and you will be able to change your APN settings on the fly by simply looking up the carrier you wish to use.

http://www.unlockit.co.nz/unlockit/

These might be the settings you need:

Syria
Provider Name Syriatel
Provider APN mms.syriatel.com
WAP 1.0 Gateway 172.20.5.6
MMSC http://mymms.syriatel.com/