How to update your iphone's IOS but keep your cydia data and files?

So I want to get Ac! D Siri but I must have IOS 5.1.1 and I have IOS 5.0.1. I really want to update but I have a TON of cydia apps and tweaks that I want to keep. Can you tell me how to keep them or direct me to a video please? All good answers are greatly appreciated!

There's actually a way of syncing them on itunes, you tube 'how to sync jailbroken apps on itunes' and it will bring up loads of videos for you and then you can update to 5.1.1 and then you can just reinstall the apps etc it worked for me lol cos i upgraded to get siri n all, and make sure you also get siri extentions its ace: p lol