Is there a way to copy all of my settings, repos, apps and such from one iPhone to another?

My iPhone 4 is jailbroken to exactly how I want it, but I can't replicate it on the 3GS I'm using for music and video storage. I get most of the settings down, but something is weird with the icons and for some reason "Chrome Slider HD LS" will not load properly. Can anyone help me out here?