[PHP] checking if e-mail address and syntax are valid

[Carlos Fernando Scheidecker Antunes]

Hello all!

I would like to know if anyone has or know any PHP code to verify if a form entered 
e-mail address is valid?

I would like that things like 4$%^%$@@.com.br could not be sent. I only has to verify 
the syntax of it, the existance I believe should be harder to verify but if it is 
possible I would be glad if anyone could point me the way.

Thanks,

Carlos Fernando.