The Change Password dialog is confusing and difficult to use.

For instance, the light bulb isn't something one would normally associate with
authentication success/failure and valid input. I would suggest a standard
gtk-dialog-authentication stock image (locked lock) which changes to an unlocked
state when the user correctly types his/her current password.

Also, the explanatory text is changing to reflect any changes or errors in the
process, but it is difficult to notice it changing. I'm unsure how to best
improve this one. Maybe a little (visible) tooltip should appear by the entry
field which needs the users attention?

I would also suggest splitting the process in two:
- First enter your current password for authentication
- If authentication was successful, set the two new password fields to sensitive.

This is how it's done in the `passwd' program. It won't continue until you first
 enter your current password.

There should perhaps also be an inactivity timeout after authenticating the user
in case the dialog is left open, for security reasons.

Other information:
I've made a suggestion to a new password-dialog interface. It can be found at
http://joh.deworks.net/password-dialog/screenshots/password-dialog.png