SHORT DESCRIPTION This Perl module provides routines for checking validness of email address. It makes several checks: 1) it checks syntax of email address; 2) it checks if there any MX record for specified in email domain or if there exist such host; 3) it tries to connect to email server directly via SMTP to check if mailbox is valid. Old versions of this module have performed this check via VRFY command. Now module uses another check: it uses combination of commands MAIL and RCPT which simulates fake sending of email. Old VRFY is still supported. However please note VRFY can't detect bad mailboxes in many cases while MAIL/RCPT works. For example hotmail.com can be verified with MAIL/RCPT check while VRFY check doesn't work. This module was designed with CGIs in mind. It has support for check timeout so it can be used to filter fast wrong e-mail adresses in CGI forms (passing as valid e-mail addresses that can't be checked fastly). For details see pod documentation in Mail::CheckUser REQUIREMENTS This module requires next Perl modules: 1) Net::SMTP (libnet package) 2) Net::DNS (Net-DNS package) 3) IO::Handle (IO package) Perl distributions before 5.6 contain version of IO::Handle which has bugs in timeouts handling. Download latest version from CPAN if you haven't did it before. INSTALLATION perl Makefile.PL make make test make install Tests can run very slowly especially if you have network down. BUGS If you have encountered any problems with this module fill free to contact me. My email: Ilya Martynov