I hacked something together that does what I want, but I'm sure theres a more elegant solution. Please let me know. 
#!C:/Perl/bin/perl.exe

use strict;
use warnings;

use CGI;
use CGI::Ajax;

my $cgi = new CGI;

my $pjx = new CGI::Ajax( 'update' => \&update_options,
                         'update2' => \&update_options2);

my @item1 = qw(1 2 3 4 5);
my @item2 = qw(1 2 3 4 5);
 
my $html = '<HTML>
<HEAD><title>CGI::Ajax Example</title>
</HEAD>
<BODY>';

$html .= '<div id="data1"><SELECT name=\"TEST\" id="val1" onchange="up
+date( [\'val1\',\'NO_CACHE\'], [\'data2\'] );">\n';
$html .= populate_list_box(@item1);
$html .= "</SELECT><BR></div>\n";

$html .= '<div id="resultdiv"></div><hr>';

$html .= '<div id="data2"><SELECT name=\"TEST\" id="val2" onchange="up
+date2( [\'val2\',\'NO_CACHE\'], [\'resultdiv2\'] );">\n';
$html .= populate_list_box(@item2);
$html .= "</SELECT><BR></div>\n";

$html .= '<div id="resultdiv2"></div>';

$html .= '
</BODY>
</HTML>';

print $pjx->build_html($cgi,$html);

sub populate_list_box {

    my @array = @_;

    my $htmlCode = "";

    foreach (@array) {
    my $selected = "";
    $htmlCode .= "<option value=\"$_\" $selected>$_</option>\n";
    }
    return $htmlCode;
}

sub update_options {

    my $input = shift;

    my @item2 = qw(11 12 13 14 15);
    my $html = '<SELECT name=\"TEST\" id="val2" onchange="update2( [\'
+val2\',\'NO_CACHE\'], [\'resultdiv2\'] );">\n';
    $html .= populate_list_box(@item2);
    $html .= "</SELECT><BR>\n";

    return $html;
}

sub update_options2 {
    my $input = shift;

    return $input;
}

[download]

In reply to Re: cgi and update event by Anonymous Monk
in thread cgi and update event by Anonymous Monk

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.