The latest version of Redsn0w brings full support to enable multitasking and wallpapers on both iPhone 3G, and iPod touch 2G, running iOS 4 which otherwise are disabled by Apple, citing performance issues. We have already posted full detailed guides on how-to enable multitasking and wallpapers support on iPhone 3G and iPod touch 2G manually. If those guides are too long or complex for you, you can now use the latest version of redsn0w which gives you a one-click option to enable these options with ease.
Redsn0w jailbreak tool has been updated to version 0.9.5b5 which brings full support for iPod touch 2G, along with optional support to enable multitasking and wallpapers on iOS 4.0 (formerly iPhone OS 4) on iPhone 3G and iPod touch 2G which otherwise are disabled by Apple.