The Evad3rs have released Evasi0n 1.3, an update to the jailbreak utility that brings support for the new iOS 6.1.1 iPhone 4S firmware. Additionally, the team notes that OS X 10.5 should be fully supported now and the linux glibc requirement has been lowered to 2.3.
● Support for 6.1.1 on the iPhone 4S.
Here are the Evasi0n Download Links.
If you are looking to update your iPhone 4S to iOS 6.1.1 you should make a backup and properly restore your device in iTunes. Do NOT use the over-the-air update.