app/design/frontend/base/default/layout/moneybookers.xml

<moneybookers_processing_payment>
        <reference name="root">
            <action method="setTemplate"><template>moneybookers/blank.phtml --- change here!!
        </reference>

app/design/frontend/base/default/template/moneybookers/payment.phtml

<!--
<div class="page-head">
    <h3><?php echo Mage::helper('moneybookers')->__('Please pay your order now') ?></h3>
</div>
<table style="width:100%;">
    <tr>
        <td style="width:100%">
            <iframe style="width:100%; height:600px;"  src="<?php echo Mage::getUrl('moneybookers/processing/placeform') ?>"></iframe>
        </td> 
    </tr>
</table>
-->
/* invalidate iframe!!!

/*add below script!!

<script type="text/javascript" >
   window.top.location="<?php echo Mage::getUrl('moneybookers/processing/placeform') ?>";
</script>