JS Not Working In IE When Hiding DIVs

I am trying to let my user hide or show certain div's on a page. I am managing it in Firefox but IE wont do it for me. IE errors saying Object doesnt support the Property or Method? I have dynamic naming for the divs and call the script like so where you see x my array fills in the number index so the div's gets id's like myDiv(0) up to whatever.

Code:
<a href="javascript:showhide('myDiv(<%=x%>)')">Show Hide Div</a>
The Script that gets used is as follows.
Code:
<script language="javascript">
<!--
var state = 'none';
function showhide(myDiv) {
if (state == 'block') {
state = 'none';
} else {
state = 'block';
} if (document.all) { //IS IE 4 or 5 (or 6 beta)
eval( "document.all." + myDiv + ".style.display = state");
} if (document.layers) { //IS NETSCAPE 4 or below
document.layers[myDiv].display = state;
} if (document.getElementById &&!document.all) {
hza = document.getElementById(myDiv);
hza.style.display = state;
}}
//-->
</script>