What's wrong with \w and underscore?

Hi,

while using regexp 1.2 to parse a property file, I have a problem with
the _ character (underscore). I have the following code:

try {
	RE pattern = new RE("(\\w+)=(.*)");
	pattern.match("asdf_qwer=kajflkjaflksafsajflkf");
	System.out.println(pattern.getParen(1));
}
catch (RESyntaxException e) {
}

I would expect getParen(1) to match with asdf_qwer, but instead the
output of this is : 
qwer

The regexp documentation specifies that \w matches alphanumeric
including _, but somehow it doesn't work. For fun, I tried the following
similar code in Perl:

  print $1 if "asdf_qwer=kajflkjaflksafsajflk" =~ /(\w+)=(.*)/;

The output of this is:
asdf_qwer
as expected. What am I missing here? It is so big, I can't believe this
is a bug. I tried to look in the archive of this mailing list, but
couln't find anything relevant.

Thanks

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org:Imperial Tobacco
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email;internet:[email protected]
title:Senior Architect
fn:Normand Rivard
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