FUSE refuses to automount NTFS partition on SATA drive

[Shaved Wookie]

This is a bit of an odd one.

I have an NTFS formatted partition on an IDE drive and FUSE works perfectly here. (/dev/sdb3)
I have an NTFS formatted partition on a SATA drive, and if it's not set to automount, I can mount it with either the mount command or by clicking on it in the file manager and it works perfectly. (/dev/sda1)

But...

If I add "/dev/sda1 /media/seagate ntfs defaults 0 0" in fstab to automount sda1 (the same line that works with sdb3):
* I get all kinds of errors in dmesg along the lines of "Buffer I/O".
* If I click on it in the file manager I get "Only root can mount /dev/sda1 at /media/seagate".
* Trying to mount with "mount /dev/sda1" gives a message like "Error. Could not get device lock on /dev/sda1" about 5 times.
* If I boot to the recovery prompt, I get an infinite scrolling screenfull of errors along the lines of "FUSE error. Can not mount file system at /dev/sda1 [123456]"

fdisk -l does not show sda at all until I manually mount it (which I can only do by removing the fstab line and rebooting) after which it shows:
   Device Boot Start End Blocks Id System
/dev/sda1 1 182401 1465136001 7 HPFS/NTFS
/dev/sda4 * 1 1 0 0 Empty

My fstab looks line like: /dev/sda1 /media/seagate ntfs defaults 0 0

I don't see any of these errors if I boot to Jaunty, and I've done a complete chkdsk and clean shutdown in windows.

I'm on Kubuntu Karmic AMD64
KDE 4.3
libfuse 2.4.7-1.1ubuntu4(amd64)

Any ideas gratefully accepted!

ProblemType: Bug
Architecture: amd64
Date: Fri Nov 13 09:30:36 2009
DistroRelease: Ubuntu 9.10
InstallationMedia: Kubuntu 9.10 "Karmic Koala" - Release Candidate amd64 (20091020.2)
NonfreeKernelModules: fglrx
Package: libfuse2 2.7.4-1.1ubuntu4
ProcEnviron:
 LANGUAGE=
 LANG=en_CA.UTF-8
 SHELL=/bin/bash
ProcVersionSignature: Ubuntu 2.6.31-14.48-generic
SourcePackage: fuse
Uname: Linux 2.6.31-14-generic x86_64