If you are running this on Linux then you don't have to worry about the difference between "text" and "binary". 

perl -0777pe's!<div>Comments</div>!<div class="red">Comments</div>!g' 
+`find . -type f`

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In reply to Re: Replacing text in many files, including binaries by jwkrahn
in thread Replacing text in many files, including binaries by lancer

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