System preferences crashes when press accounts

I'm trying to help someone else with their computer, every time I try to access the "Accounts" settings in system preferences, system preferences hangs and then crashes, any idea what's up? The computer is a Macbook 2.4Gz Core Duo, and all the software is up to date.

-Thanks

Edit: This is what comes up in console.

2/18/11 9:25:24 PM  System Preferences[201] NSConcreteMutableAttributedString initWithString:: nil value
2/18/11 9:25:24 PM  System Preferences[201] NSConcreteMutableAttributedString initWithString:: nil value
2/18/11 9:26:37 PM  System Preferences[201] [NSPrefPaneBundle instantiatePrefPaneObject] (/System/Library/PreferencePanes/Accounts.prefPane): should only be called once

You might get better answers if you provide more information such as when this started happening. For example, did you add a new account recently? Install any applications recently?

Normally, when weird stuff happens on OS X such as crashes, repairing permissions can be a good place to start. Try opening Disk Utility and select your computers Hard Drive on the left hand side, then click 'Repair Permissions'. This will take a few minutes and may solve your problem. Try a restart after the repair before you go back into Accounts.

Have you tried this under a different user account? I've come across instances of people having this only occur on one account. You could create a new account and restore documents etc from a backup.