INVITE A FRIEND SCRIPT FOR A PHP WEBSITE

We are building a registration process of new website. And we want to add the functionality SEND TO A FRIEND. This functionality have to make that the customer can IMPORT his addresses from his GMAIL, YAHOO, HOTMAIL Email ( a pop up ll open and he have to put inside his email username and password for each email). Then he can import all addresess from them or each of them (for example GMAIL) and send a message for inviting them to this website. The website is written in PHP actually Please answer ONLY if you have just done this kind of script and you can reference it in an online website. You can for example take inspiration from the [login to view URL] process of registration for undestand what i mean