How to mask input from user in inputfield

[Robby Pelssers]

Hi all,
 
i was just wondering how I can easily mask user-input entered into a
field-widget.  I need this for a inputfield where the user enters a
password.  I am planning on creating redundant password-field (also
required) and compare them before writing information to the database.  
 
But the actual question is: ... if user enters "pwd"     , how can i
accomplish that he sees "***" in input field?
 
Thx in advance.
 
Robby Pelssers