I had the same problem when I switched to android 4.x.
On gingerbread everything worked fine, though.
Anyway, I just found the solution to my problem.
>> Menu/Settings/Wireless connections/Mobile networks
Make sure that the first lines (Data Roaming, 2G only, 3G only, Disable connections) are not checked.
First, go to Network Operator (or similar)
let your phone search for networks (may take several minutes)
once the networks are found, select the bouygues télécom network, usually written out loud, with an F or France, sometimes seen: Bouygtel France.
Once selected you will have: Recorded on bouygtel France
then Recorded on the network.
You will be automatically redirected to the mobile network settings.
Now we go to Name of Access Points just below.
A single APN is enough for MMS, Internet, Mail
done: Menu / new APN:
Proxy MMS: 062.201.129.226
MMS port: 8080
Authentication type : PAP
APN Type: internet+mms
For SMS, no configuration required (normally),
otherwise the sms server (or SMSC) is: +33660003000
Restart the phone and everything should work.
Hoping I might have been able to help some of them…