[mycontext]
        ; You could do it with just one Goto
        exten => _NXXXXXX,1,Set(MYEXTEN=234${EXTEN})
        exten => _NXXXXXX,2,Goto(mycontext,${MYEXTEN},1)

        exten => _234234XXXX,1,Dial(Zap/g0/${EXTEN})
        exten => _234235XXXX,1,Dial(Zap/g0/${EXTEN})
        exten => _234236XXXX,1,Dial(Zap/g0/${EXTEN})

~
~
~