multiple inner join error

[culonbu]

SELECT FUNCTIONS.FUN_NAME, FUNCTIONS.FUN_ID, FUNCTIONS.FUN_NAME,
EQUIPMENTS_FUNCTIONS.EQUIP_DESCRIPTION, HIRE_EQUIPMENTS.HEQUIP_DESCRIPTION,
STAFFS.EMP_TITTLE
FROM FUNCTIONS,EQUIPMENTS_FUNCTIONS,FUNCTIONS_HIRE_EQUIPMENTS,FUNCTIONS_STAFFS
WHERE FUNCTIONS.FUN_ID = 'F20031235'
and
FUNCTIONS.FUN_ID = EQUIPMENTS_FUNCTIONS.FUN_ID
and
EQUIPMENTS_ID.EQUIP_ID = EQUIPMENTS.EQUIP_ID
and
FUNCTIONS.FUN_ID = FUNCTIONS_HIRE_EQUIPMENTS.FUN_ID
and
FUNCTIONS.FUN_ID = FUNCTIONS_STAFFS.FUN_ID
and
FUNCTIONS_STAFFS.EMP_ID = STAFFS.EMP_ID