earlier i got this email from tesco mobile ireland
on mms setup
1. If you have an iPhone 4 get a Tesco Mobile Micro SIM. Call Customer
Care on 1749 or 0894200000 and they can get one sent out to you. You
will need to call them back when you get it to get your number
transferred to the SIM.
2. Put the Tesco Mobile SIM in unlocked iPhone and perform normal setup
3. Go to Settings->General->Network and Turn Data Roaming On
4. Also in Settings->General->Network go to Mobile Data Network
Put APN and MMS proxy details in as below
a) Enter the following details into Mobile Data at the top of the
Username: leave empty
Password: leave empty
b) Enter following details into the MMS section.
MMS Proxy: 10.1.11.19:8080
Max Message Size: 307200
MMS UA Prof URL : leave empty
Reboot your handset and you are now configured for the Internet.