HD Install :: How to undo 'mkswap /dev/hd3'

Is there any way to undo the command "mkswap"?
I tried to delete the partition but when i made a new one it was allways used as a swap partition.

Also is there any reason why sometimes fdisk and cfdisk can't open "hda" and "hdb" i just get fatal errors.

if you mkfs the partition it will stop it being swap.

original here.