You're not putting a blank line between your headers and body.

Also, this is a FAQ. How do I send mail?

Notice that the example just uses a "From:" header in the message. I don't see why that wouldn't work.

Why don't people read the FAQ any more?

Also. Why use:

$mailto[0]="person1\@gmail.com";
$mailto[1]="person2\@hotmail.com";
$mailto[2]="person3\@yahoo.com";
[download]

Instead of:

$mailto[0]='person1@gmail.com';
$mailto[1]='person2@hotmail.com';
$mailto[2]='person3@yahoo.com';
[download]

Or even:

@mailto = qw(
             person1@gmail.com
             person2@hotmail.com
             person3@yahoo.com
            );
[download]