There's some information about the browser that you can usually find in the server's variable $ENV{'HTTP_USER_AGENT'}
In my case that is "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1)", but I've seen other signatures in my logfiles. With the opera browser, it's possible to write a user agent yourself in the browser's preferences. Maybe this is even possible for internet explorer. So you could maybe add _nikolas.tk_ at the end, then your script can look for that signature. You should not erase the Mozilla/4.0 part or otherwise you might get problems when other websites think you're using an outdated browser.

Anyway, I think like others already said, best you just kick the counter out! Best way to really count visitors on a web site is to analyse the server logs (with a system like webalizer or with a custom script) so you can count out the search engines as well.
BTW if you want to make some other improvement to the site, why not add an English version?