i have a iphone the firmware is 3.1.2.. my cydia hasn't been working for a while but i didn't want to restore my phone because i don't want to lose anything at all. i know i can back it up, but when i back it up will it keep my theme?? that's what i'm worried about mostly. if i back it up, will EVERYTHING stay the same or will i have to install all the things i've done through cydia and winterboard all over again?

the only reason i need cydia now is because my lock button won't work and i need the app ishakelock.. so. any insights?

thanks soo much in advance!