I have a unlocked (ultrasn0w) + jailbroken (redsn0w) iPhone 3G. I enabled multitasking through redsn0w. It was working awesome at first but after I installed some packages from cydia, the multitasking just stopped working. Multitasking works fine in Safe Mode, which probably means than some springboard extension was doing something.
(Update)
Also, the icon labels on my home screen are gray and have no shadows. That doesn't happen in safe mode. When I try to double-click the home button in an application, it just freezes for a few seconds and returns to where I was. If I do it at the home screen, the multitasking bar appears at the bottom of the screen but it's completely blank. These are the packages I've installed off of cydia:
Activator
Autolock SBSettings
Cycorder
GV Mobile
MakeItMine
SBSettings Tethering toggle
ultrasn0w
VoIPover3G
WinterBoard
xGPS
3G EDGE (for WinterBoard)
The italicized ones are the ones I've tried uninstalling.
(Update)
Also, the icon labels on my home screen are gray and have no shadows. That doesn't happen in safe mode. When I try to double-click the home button in an application, it just freezes for a few seconds and returns to where I was. If I do it at the home screen, the multitasking bar appears at the bottom of the screen but it's completely blank. These are the packages I've installed off of cydia:
Activator
Autolock SBSettings
Cycorder
GV Mobile
MakeItMine
SBSettings Tethering toggle
ultrasn0w
VoIPover3G
WinterBoard
xGPS
3G EDGE (for WinterBoard)
The italicized ones are the ones I've tried uninstalling.