iPhone Dev Team’s front man MuscleNerd has announced that the current version of Redsn0w can jailbreak iOS 5.1.1 on older devices. Remember its a tethered jailbreak only.
We suggest jailbreakers to stay on their current version instead of updating to iOS 5.1.1. But if you have already updated to the new firmware or previously using iOS 5.1 that also had tethered jailbreak solution only, then you can jailbreak 5.1.1 using the latest version of Redsnow.
Another thing to be noted is that this tethered jailbreak is only for older devices so DO NOT update iPhone 4S, iPad 2 and the new iPad to iOS 5.1.1 because Redsn0w won’t be able to jailbreak these devices.
Latest version of Redsn0w was released two days back with minor bug fixes. Download links are provided below: