Mail password problem

I have been having an issue with Mail.app.

After I create an account, even if i do define the password (whether it be via programmatically doing so using applescript OR manually), after I save my changes and close the "Preferences" frame for Mail in which the password can be changed, the password text box resets to be blank. NONE of the other properties change (the username, email, servers etc all are saved and do not reset to be blank text boxes). Here's a visual of the preferences frame with the blank password box issue:

As you can see, the password box is blank and even if i manually change the password and save changes, when I re-open the same preferences window after closing it, the password box is blank once again.

Here is a screenshot of the "Advanced" settings pane: