I just got a USB to IDE drive from geeks.com

My slackware 10 system seems to work fine with it. My Xandros 2.0 system, however, doesn't

It reads from it fine, however it locks up whenever it has to write to it for more than a second. Here's it's dmesg init:

USB Mass Storage device found at 5
scsi singledevice 1 0 0 0
Vendor: TOSHIBA Model: MK4025GAS Rev: 0811
Type: Direct-Access ANSI SCSI revision: 02
Attached scsi disk sda at scsi1, channel 0, id 0, lun 0
SCSI device sda: 78140160 512-byte hdwr sectors (40008 MB)
/dev/scsi/host1/bus0/target0/lun0: p1

It is connected to a 40 gig toshiba laptop drive. Any ideas?