why not use a custom dialog, which supports the input of fields with password masking and will not refresh the page with each keystroke?
Mike's suggestion of a Custom Dialog is the only option for password fields in WebDirect, OnObjectKeystroke is one of the few script triggers not supported through WebDirect unfortunately.
Thank you Mike and Orlando,
Since users experience will be different when they do login with custom dialog. Anyway, I'm going to use custom dialog for now.