Here are the settings required to use your T-Mobile sim in your iPhone 3GS. Note, the iPhone must already be jail broken and unlocked. Head over to iPhone Dev Team for more information on jail breaking.
- Using Safari browser on the iPhone, go to "help.benm.at" … scroll down to "Features" and select "Tethering"
- Scroll down the list of countries and select "Create your own Generator"
- Enter the following text in the "Carrierdata" form:
- Deselect the optional "Webclip" and click on Download.
- Accept and Install the settings … BUT DON’T reboot yet.
- Go into Settings > General > Network > Cellular Data Network >
- Populate the fields as below:
Note: Celluar Data should already be populated, but I’ve listed it here just in case.
MMS Proxy 188.8.131.52:8080
- Exit out of these settings back to your home screen and perform a hard reboot (hold down Home and Power until the iPhone Reboots)
- Once rebooted you should be set. Send yourself an MMS message to check. Also in Settings > General > Network … you will notice "Internet Tethering" option.