Well first things first take a look at the documentation.
code:
OnEvent_ContactSignin(
[string] Email
);
Notice the function passes the email address as a parameter. Therefore the code you use is
code:
function OnEvent_ContactSignin(sEmail){
Debug.Trace(sEmail);
}
Also to note that the Contact and Contacts objects are only available when you enumerate or use the Messenger.MyContacts.GetContact function.
To enumerate the object you need to do the following:
code:
for ( var oContact = new Enumerator(Messenger.MyContacts); !oContact.atEnd(); oContact.moveNext() );
Debug.Trace( oContact.item().Email );
}
And to use the GetContact function it looks like this
code:
Debug.Trace( Messenger.MyContacts.GetContact( 'johndoe@hotmail.com' ).Email );