Apple released iOS 5.1 few days back.
iPhone iPhone Dev released Redsn0w 0.9.10b6 for tethered jailbreak on iOS 5.1 which supports iPhone 4, iPhone 3GS, iPad 1 and iPod Touch 3G/iPod Touch 4G.
Now iH8sn0w has also released Sn0wbreeze 2.9.2 which also has no support for A5 devices.

Change log for iH8sn0w’s Jailbreak tool
Added Tethered Jailbreak support for 3GS/iPod Touch 3/A4 Users on iOS 5.1 (9B176)
iPhone 3GS old-bootrom users are untethered on 5.1/9B176 (as usual).
Bug Fixes (Specifically with the iPad baseband and iPhone 2G).
Re-added the iPhone Dev-Team’s iPhone 2G permanent unlock ‘BootNeuter’.
For those who are unaware Sn0wbreeze works like Pwnage Tool for Windows.
Download Sn0wbreeze 2.9.2 for Windows
Download Sn0wbreeze 2.9.2 for Windows