This is more of a javascript question, but you could try something like this untested code:

in the popup

<form action="#" onSubmit="submit_it(this);">
 ....
</form>
<script language="javascript">
function submit_it(form) {
 for (var i=0; i < form.elements.length; i++) {
   opener.forms[0].elements['hidden_'+form.elements[i].name].value = f
+orm.elements[i].value;
}
</script>
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and then add hidden fields to the form in your opener named 'hidden_[name_of_field_in_popup]'

ofcourse if you use things like radios, checkboxes or select fields, you need to test for those too.

Take a look at PPKs javascript section for much more information on coding javascript.

An other technique could be to open the popup with the data from the opener in hidden fields... i cannot really say what the best solution would be without more info.

-- 
Joost       downtime n. The period during which a system
            is error-free and immune from user input.
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