I find the easiest way to do this is to mark the closing tags with a unique character - I usually use an asterisk, but it can be any other character that doesn't exist in the rest of the file. 
$lines =~ s/(<\/a>)/\*$1/gms;

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Then I search for two open tags without that character between them. 
$lines =~ /<a[^\*]*<a/gms;

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In reply to Re: how do i find unclosed tags ? by amarceluk
in thread how do i find unclosed tags ? by s0n1c

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