Disable swapfile encryption on Maverics does anyone know how to disable the default encryption of the swap file ?

i tried this by setting the default preferences 

$ sudo defaults write /Library/Preferences/com.apple.virtualMemory DisableEncryptedSwap -boolean yes


but this doesn't work :(

$ sysctl vm.swapusage
vm.swapusage: total = 1024.00M  used = 0.00M  free = 1024.00M  (encrypted)


any ideas ?
The option to disable the encryption was removed in recent versions of dynamic_pager.