Fixing periods and commas parsed into urls?

[Gutspiller]

When you post www.blah.com and it's in a sentenced sometimes people put a comma or a period and many other characters. Is there a way to fix this so that it doesn't do it without just tell people to not put periods and commas, etc. after urls? I know that it needs some characters because of database urls to other places and dynamic urls, but is there a way to fix this?

Any help would be greatly appreciated.

Thanks!