How to use the unauthenticatedIdentity property

[Andrey Rybak]

Hello

How to use this property, which can be specified in the login-config.xml
as a parameter of a LoginModule:

<module-option name = "unauthenticatedIdentity">guest</module-option>

Am I right that the j_username and j_password parameters must not be submitted at all, so that the LoginModule will get a null values trying to retrieve them?

If so how to achive this -- how to cause a form not to submit some of its input fields ?
An attempt to intercept and cancel a submit request in javascript, calling the function "open('j_security_check', 'top')" instead fails.

Best regards.