I have a problem with field: Options->Personal Information->E-mail Address.
In that field I can write just any address and it will be sent without problems - for example
whatever@whatever.com - and my postfix will send it.
My users names are the same like emails.
Is there any option to change behave of squirrelmail - and when user is sending email it alaways is sending using his user name whatever field "e-mail address" contain?

I know that I can remove that option from /squirrelmail/include/options/personal.php script but in specific cases cookies from IE, Firefox are messing with /var/lib/squirrelmail/data/users.pref files. And that files contains information about this address.