UPDATE 05/12/2008 : Fixed validate onBlur bug
UPDATE 25/10/2008 : Fixed set value bug
UPDATE 18/10/2008 : Fixed resize bug with formdata 100%
UPDATE 1/7/2008 : Added to source/download : Apache License, Version 2.0
Another User Extension contribution - PasswordField (see screen shot attached). Credit goes to http://extjs.com/forum/showthread.php?t=20417 for providing the concept and idea - though not much was shared other than the images.
Add the PasswordField.jar to your lib and the following line to your gwt.xml
Code:
<inherits name='ext.ux.pwd.PasswordField'/>
The code snip below shows how to use it within a normal FormPanel or FormLayout.
...enjoy,
Grant 
Code:
final PasswordField pw1PwdFld = new PasswordField();
pw1PwdFld.setEmptyText("Enter a strong password");
pw1PwdFld.setFieldLabel("Secure Password");
pw1PwdFld.setMinScore(PasswordField.Strong);
formpanel.add(pw1PwdFld);