SOLUTION:
no need to use redsnow there's a simple tweak to enable multitasking gestures on ipad,follow the instructions and everything will be fine.
for this u need ifile
after this open ifile and navigate to System >> Library >> CoreServices >> SpringBoard.app >>
K48AP.plist
Select the file
K48AP.plist and use Property list viewer to edit the entries
Inside the file go to capabilities
Locate the option for multitouch gestures and turn it on
Close ifile and respring the device
Go to settings/general and u should see the gestures option already enabled
Smile and enjoy multitouch gestures
if u need pics just tell me,hope i helped u here