Partitioning a drive in XP

I currently have a computer running both XP and Windows98. I had the computer set up by a friend,but,when he partitioned the drive(which is 40Gigs)he made it have 3 partitions ,with C: having 5Gigs,D:having 8 Gigs,and all the rest in E:. Would it bepossible to re-partition the drive without re-formatting it? Or,is there no other way of doing that?Thanks to all in advance.