There is an alternative way to resize/create/delete partition(s) on the flash card. Since all of you are using either virtual machine or live cd, why not download and install gparted ? If you use ubuntu live cd, it's already installed there. If you are using vmware, and your system is based on debian, just type "sudo su" then "apt-get update && apt-get install gparted"
and then don't close the window and type "gparted".