This vides shows How to Upgrade your iPhone 3g or 3gS running any firmware lower than 4.1 Firmware. It could be 3.0, 3.1, 3.1.2, 3.1.3, 4.0, 4.0.1, 4.0.2. First thing you need is Redsn0w 0.9.6b5 to start whole process and to put our device in DFU mode. Once Redsn0w has sent our device in DFU state then simply close Redsn0w and Open iTunes and upload 4.1 Custom Firmware file. Download Redsn0w for WINDOWS: uploading.com Download Redsn0w for MAC: uploading.com IF above Redsn0w gives you issues while running, then run these versions of Redsn0w Mac: uploading.com Windows: uploading.com Here are the Official/Stock 4.1 Firmwares for iPhone 3g/3gS/4 that you will browse in Redsn0w. Download here iclarified.com Below are the CUSTOM FIRMWARE FILES THAT YOU NEED to Upload through iTunes on your respective iPhones Custom 4.1 firmware for iPhone 3g uploading.com Custom 4.1 firmware for iPhone 3gS uploading.com Custom 4.1 firmware for iPhone 4 www.4shared.com After above Custom firmware file is uploaded according to your device, then simply open Cydia and install “Ultrasn0w”. You will be fully Unlocked this time. Now you can use your UnOfficial sim card in your respective devices. Get MMS Settings for Tmobile/Simple Mobile by adding source in Cydia ” beta.leimobile.com ” Then install “T-Mobile MMS Fix/Simple Mobile MMS”. Reboot now. Then go to your ‘settings’ on your iPhone then ‘general’ then ‘Network’ then ‘Cellular Data Network’. Here enter these settings just under MMS twitpic.com …