Basic Web Hacking Suggestion

As I was trying to solve the problem of why my anonymous emailing PHP script wouldn't work, it gave me an idea for a Basic Web Hacking challenge. Now, I just thought of this out of the blue so it's very vague but it could be something like this. You must send an email from a specific admin from a specific domain (e.g. admin@hacker.com) with an IP in the right range. I'm not very good at coding, myself, but for someone who is, I'm sure this can't be too hard :p So the code could verify that the email came from admin@hacker.com and that it has an IP in the right range, so it's realistic (if it doesn't come from an IP in the range then it can't be the admin). Give some feedback and we can elaborate on it :)

Well, the idea is very broad and impossible sounding, but I was hoping someone could speculate and think of a way to make it work, one way or another.

that might work, but the problem would be recieving hte email and checking it.

it might be quite hard to setup a script that listens for incomming emails from a certain address, and it could clog up the webmail, if a scritp gets stuck in a endless loop.

Well, the script doesn't necessarily have to accept an email. Just some way that it checks to see that you made a PHP script that would deliver an anonymous email, or something like that.

We could do this as a "Other Challenge"

where they would submit a page, where the php file is highlighted.

Yeah, that could work too.