Problems with file corruption on C240

[James Stocks <stocksy@stocksy.co.uk>]

Hi,

I'm trying to run Sarge on my C240, but I've hit a roadblock.  The  
installation routine completes fine using the minimal CD and it will  
reboot into the new Debian install, but after a day or two it eats my  
files.  The problem can be quickly reproduced by doing something like  
repeatedly compiling the kernel or using 'stress'.

Here some (hopefully relevant) lines from dmesg:

EXT3-fs error (device sda5): ext3_free_blocks: bit already cleared  
for block 249189
EXT3-fs error (device sda5): ext3_free_blocks: bit already cleared  
for block 249190
EXT3-fs error (device sda5): ext3_free_blocks: bit already cleared  
for block 249191
... repeats many times

EXT3-fs error (device sda5) in start_transaction: Readonly filesystem
... repeats many times

If I reboot, it remounts the filesystem as read/write.  Sometimes  
everything is fine, sometimes a load of stuff shows up in /lost 
+found, and sometimes it just refuses to boot and I have to reinstall.

Is this caused by my stupidity or is it the hardware?  I'm confident  
that I've got the FWSCSI chain terminated properly, there are no  
other devices on the chain and the HD has an ID of 5.

Any help will be appreciated!

Thanks,
James.