public function loadItemPropertiesMultipleOwners( $serials_by_owner )
	{
		// make sure we have something to look up.
		if ( !is_array($serials_by_owner) || count($serials_by_owner)==0 )
		{
			$this->set('properties',array() );
			return false;
		}
		
		// get the properties.
		include_once(DIR_CLASSES . '/itemnorm/propertyreader.php');
		
		$properties = !$this->isempty('properties') ? $this->get('properties') : array();
		foreach ($serials_by_owner as $owner=>$serials) 
		{
			$pr = new PropertyReader( );
			$new_properties = $pr->getProperties( $serials, $owner );
        	if( !is_array($new_properties) ) {
				throw new CircuitExecutionException('Could not retrieve the properties of the current serials.');
			}
			foreach ($new_properties as $serial=>$prop)
			{
				$properties[$serial] = $prop;	
			}
		}
		
		// save for later
		$this->set('properties',$properties);
		return TRUE;
	}