Disclaimer: I don't have a scanner, so I'm not able to actually verify that the following solves the problem of users not being able to access their scanners 'other than as root,' but I'm sure someone who does, and is or has had trouble accessing their scanner can test and update this. (Using Hardy Heron 32-bit)
K Menu > System Settings > User Management > Administrator Mode
Click your Login Name and then the Modify... button
Click on the Privileges and groups tab
Check Use scanners box
K Menu > System Settings > User Management > Administrator Mode
Click your Login Name and then the Modify... button
Click on the Privileges and groups tab
Check Use scanners box