If you're on Linux, you could use the xmllint command: 
$ xmllint --noout --valid foo.xml

[download]
Or you could use XML::LibXML: 
my $parser = XML::LibXML->new;
$parser->validation(1);
eval {
  $parser->parse_file('foo.xml');
};
print $@ if $@;

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In reply to Re: XML parsing errors - finding them by jczeus
in thread XML parsing errors - finding them by ethrbunny

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