That's what I was afraid of...
For now I've compromised on this. I used the "tell a friend" form from bignosebird.com and removed the place where it is supposed to automagically insert the page url. Instead it
simply inserts the url
http://www.railroadforums.com/ no matter what page they call it from. (and of course I changed the wording to tell a friend about this site...)
So, no matter where they use it, the url won't break. Bad news is that it doesn't allow you to send a specific page, just the site in general.
Any cgi hackers out there know an easy way to strip the "S=" portion out of the url? If I can do that, I could make this script work.