APEX

All I have created an html region with the following button attributes:
<input type="BUTTON" value="Create New" onClick="popupPage('f?p=&APP_ID.:42:&APP_SESSION.::NO:::');" target="_blank">

I have created a clear cache process "Before Header" that should clear all page items on Page 42. Unfortunately it does not work and I was wondering if I am doing something wrong.

I know you can create an actual button on the page and then get it to clear cache on the target page when submitted but I need to use an html button as I have a popup javascript attached to the page where the "Create New" button resides.

<SCRIPT LANGUAGE="javascript">
<!--
function popupPage(url)
{
w = open(url,"popPage1","Scrollbars=1,resizable=1,width=800,height=750");
if (w.opener == null) w.opener = self;
w.focus();
}
-->
</SCRIPT>

Can anyone advise how to clear cache successfully?