Windows problem of loading LIBEXPAT.dll

Hello,
 
I am trying to run a simple perl script that needs libexpt.dll.
The script just works fine if it runs in command line.
Howeber, when I try to run it under cgi-bin, like
http://localhost:8080/cgi-bin/ws/try.pl
 
there comes an error with this message: "This application has failed to start because LIBEXPAT.dll was not found. Re-installing the application may fix this problem."
 
My systems is WinXP, and runs Tomcat, and ActiveState perl.
 
Here's the perl code. Any help would be appreciated.
 
Il-Hyung
 
===========
#!perl
use warnings;
use strict;
use CGI qw(:standard);
use SOAP::Lite;
 
my $cgi = new CGI();
my %params=();
 
print ( header(), start_html("Access to Temparature Convert Service") );
 
my $temp = $cgi->param('celsius');
 
print SOAP::Lite
    -> uri('http://www.soaplite.com/Temperatures')
    -> proxy('http://services.soaplite.com/temper.cgi')
    -> c2f($temp)
    -> result;
 
print ( end_html() );