Also, you won't ever get the underscore to show up in your forum name. People sometimes wonder why I actually use it; I just like to keep a consistent online alias.
Also, look on the bright side - back when I first joined, you couldn't start a page with a number, and a few of my edits were actually credited to _Footsteps. That was weird. And after a while, it just becomes second nature to tell folks that you're actually at a different Troper page than you'd think.
Also, if you want, you can always just put the real link to your Troper page in your signature.