function openwin( page, target, width, height )
{
	var scrWidth = window.screen.availWidth;
	var scrHeight = window.screen.availHeight;

	var features = '';
	features += 'width=' + width + ',height=' + height;

	var left = ( scrWidth / 2 ) - ( width / 2 );
	var top = ( scrHeight / 2 ) - ( height / 2 );

	features += ',left=' + left + ',top=' + top;
	features += ',resizable=yes';

	window.open( page, target, features );
	return false;
}