You could use KDE Parted or GParyed. Both use the same basic code (I don't remember the original partitioning tool the code is borrowed from) but just with KDE or GNOME as the GUI on top. They're LiveCDs so you have to reboot and run off them. Maybe they could work via virtual machines. I've never tried it. You could also use Microsoft's built in partition manager to do the job. I think it might be in XP. It's definitely in Win 7 & 8.
Windows one won't let me go beyond my 1.4TB partition lol.
I'll try them if this other program doesn't work.