*TheDoctrineORMFrameworkusesthesameclassnamingconventionasPEARandZendframework,wherethenamesoftheclassesdirectlymaptothedirectoriesinwhichtheyarestored.TherootleveldirectoryoftheDoctrineFrameworkisthe"Doctrine/"directory,underwhichallclassesarestoredhierarchially.*Classnamesmayonlycontainalphanumericcharacters.Numbersarepermittedinclassnamesbutarediscouraged.Underscoresareonlypermittedinplaceofthepathseparator,eg.thefilename"Doctrine/Table/Exception.php"mustmaptotheclassname"Doctrine_Table_Exception".*Ifaclassnameiscomprisedofmorethanoneword,thefirstletterofeachnewwordmustbecapitalized.Successivecapitalizedlettersarenotallowed,e.g.aclass"XML_Reader" is not allowed while "Xml_Reader" is acceptable.