What seems to be the problem? I just created a anchor tag with a plus sign, after a ? so it is in the query section of the url where it is allowed.
Can you describe the problem better?
I tried this out in a txt file. While there is some underlining going on, nothing happens on a click that would not happen with non url text. Now when I right click there is a option to open the location. I can’t find what function is responsible for that. Nothing in help files either.
Here is a user supplied macro that may be of help.