3g jailbroken 2.2 with baseband 1.45, How do I upgrade baseband without loosing data

[santacr]

Hi,
I got a 3g jailbroken 2.2 with baseband 1.45, as I used pwnage to jailbreak given the big don't upgrade the baseband scare. So now unlock is available and I need to get it to baseband 2.28 for yellowsnow to work, as I understand it.

Is there some way to just upgrade the baseband so I can use the unlock and keep all my jailbroken settings and apps?

Do I have to restore and quickpwn with 2.2 and start over?

I would really like to avoid reinstalling all the jailbroken items like categories, themes, etc. Is that possible and still get it unlocked?

Thanks

[cpjr]

It requires a restore....so you will have to redo everything.

[santacr]

Does a step by step exists anywhere?

[dejawoo]

1-Upgrade your itunes to 8.x first.
2-If you keep your cydia apps&install aptbackup from cydia and run it to backup your apps.
3-Sync with itunes&do the full backup.
4-Go to itunes&restore with 2.2 stock-official fw(it will upgrade your baseband to 02.28.00).But you will lose about 500 mb of disk space till you finally restore it again.But this is the one way to upgrade it to 02.28.00.
5-Use quickpwn to jailbrake.
6-Using Cydia,install aptbackup.Install open ssh for any case.
7-Restore your backup from itunes.
8-Open aptbackup&hit the restore all cydia apps.
9-Install yellowsnow from cydia&unlock it...