If I remember my IRC discussion from the other day correctly, Lernid does not currently use a regex for this. You can get around this by converting the nick to lowercase and then checking if it matches. I can also confirm that nicks are case insensitive on IRC. This means that since I have nhandler registered, I can go ahead and use NHandler or NHANDLER as well; they are all the same, and only one person can use it at a time.
If I remember my IRC discussion from the other day correctly, Lernid does not currently use a regex for this. You can get around this by converting the nick to lowercase and then checking if it matches. I can also confirm that nicks are case insensitive on IRC. This means that since I have nhandler registered, I can go ahead and use NHandler or NHANDLER as well; they are all the same, and only one person can use it at a time.