in my experience, there are times when emptying the cache does not reset the favicon. i can not say which browsers honor it or not; or whether it was my user error which informed my experience (another distinct possibility). but as silver originally stated, he had tried clearing his cache in his OP.
in addition, while i have NOT downloaded his specific template, but i DID look at his site and there was no link tag for the favicon, hence my "dirty" solution which resolved his problem, and did NOT put a second link tag.
in looking at your code above, and based on what i saw on your site, silver, you have not defined FAVICON in your ZC install which is why there was no tag. which in most cases is unnecessary if you are using the default file name for your favicon; which you are.
at this point, you can safely delete the line you added this morning, and if you want, add this line to the language meta_tags.php as dictated in the link drByte sent.
define('FAVICON', 'favicon.ico');
minor sort of issues, perhaps some housecleaning, but in end up to you what you want to do.
best.
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