Slow transfer to USB hard drive?

Anybody have an idea as to why my external USB hard drive (WD 80GB, USB2.0 compatible) would be really slow with transferring files to it? I'm running SuSE 7.3 with 2.4.16 kernel (from ftp.suse.com) on a Thinkpad T30 notebook. It's not USB 2 compatible, but the drive works with it still. FYI, I'm getting an average of 50-60KB/sec transfer rate. What should I be getting if it were working correctly? Thanks. - Greg