I'm just curious as to why you're using the many if statements.
I suppose the following should work: 

$data=~ s{<rstate>[^<\n]+</rstate>}{<rstate>$new_text</rstate>}g

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Note the use of the 'g' modifier.
If you want to learn more about regular expressions in general, then Friedl's book is a must. It's one the most well-written books I've ever read on any subject and I highly recommend it.

In reply to Re^3: regex: Need help substituting by Joe_
in thread regex: Need help substituting by the_perl

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