smtp email is sent anyway

[eluser]AlphaGirl[/eluser]
Hi,
i set my form to send email with smtp setting:
user, password, host, port etc..
But even if eg. the password fail (coz i change it on purpose) the email is sent anyway.
The debugger says that the smtp fail but the email is sent..
Is it normal? Should i do any extra checking?
Maybe i misundrstood the meaning of smtp..
Thanks a lot for you help.