static public function listActions($filter = null, $return_keys = false)
	{
		$startswith = array(
			'QUICKBOOKS_IMPORT_', 
			'QUICKBOOKS_QUERY_', 
			'QUICKBOOKS_ADD_', 
			'QUICKBOOKS_MOD_', 
			'QUICKBOOKS_DEL_', 
			'QUICKBOOKS_VOID_', 
			);
			
		$constants = array();
		
		//$inter_key = 'QUICKBOOKS_INTERACTIVE_MODE';
		//$inter_val = QUICKBOOKS_INTERACTIVE_MODE;
		/*
		if (is_null($filter))
		{
			if ($return_keys)
			{
				$constants[] = $inter_key;
			}
			else
			{
				$constants[] = $inter_val;
			}
		}
		*/
		/*
		else if ($return_keys and QuickBooks_Utilities::fnmatch($filter, $inter_key))
		{
			$constants[] = $inter_key;
		}
		else if (!$return_keys and QuickBooks_Utilities::fnmatch($filter, $inter_val))
		{
			$constants[] = $inter_val;
		}
		*/
			
		foreach (get_defined_constants() as $constant => $value)
		{
			foreach ($startswith as $start)
			{
				if (substr($constant, 0, strlen($start)) == $start)
				{
					if (!$return_keys)
					{
						$constant = $value;
					}
					
					if (!is_null($filter))
					{
						if (QuickBooks_Utilities::fnmatch($filter, $constant))
						{
							$constants[] = $constant;
						}
					}
					else
					{
						$constants[] = $constant;
					}
				}
			}
		}
			
		sort($constants);
			
		return $constants;
	}