<GleamTech:DocumentViewerControl ID="documentViewer" runat="server" 
        Width="800" 
        Height="600"
        Resizable="True">
        
   <ClientEvents Loaded="documentViewerLoaded" />

</GleamTech:DocumentViewerControl>        
        
<script type="text/javascript">
    function documentViewerLoaded(sender, e) {
        var documentViewer = sender;
        documentViewer.setToolMode("Pan");
    }
</script>