Backing up App store apps

[drvsafe]

I purchased an iPhone 3g used and it came with some great apps from the Appstore. How can I back these up from my iPhone so I can then upgrade to 2.2 and unlock with yellowsn0w? Better yet, is there a way to do it? I tried to sync and back up in itunes, but it doesn't do it.
I am currently running 2.1 with 2.11.07 and using a t-mobile SIM with a Gevey proxy SIM and everything runs great. I would almost not unlock if I couldn't save the apps, its about $300 worth of appstore apps.
Any thoughts?

 

[Shader]

Just curious, did you pay extra for the apps?
Also, unless the previous owner of the device (and the itunes account) gave you their itunes account I'm pretty sure you can't reinstall the applications.

 

[skubish]

Just curious, did you pay extra for the apps?
Also, unless the previous owner of the device (and the itunes account) gave you their itunes account I'm pretty sure you can't reinstall the applications.

Yep you won't be able to keep them without having the iTunes account they were purchased with unless they are cracked apps.