[kde-linux] Device permissions

[cwh]

I am running SuSE 10 + KDE 3.4.2.  I have 'sane' and 'xsane' installed, which 
I use to access my scsi scanner (/dev/sg0).
This device is owned by root and belongs to the group 'disks'. I, as user, 
also belong to this group.   For xsane to access the scanner the group must 
have read + write permission, but the default permission for group is read 
only.
So my problem is that I have to alter the permission every time I wish to 
access the scanner.  Such alteration only survives for the session and when I 
next boot up  the permission has reverted to the default.   Presumeably, in 
order to make the altered permission premanant,  an entry must be altered or 
made in some file, but which file and where?   Can any person with more 
knowledge than me please assist?

Thanks in advance

Chris.