SIP/XXXX&SIP/XXXX do not work

Hi, I need to make run two or more SIP Phone in the same time.

But I use SIP/XXXX&SIP/XXXX but it do not worked the both.

Check my extensions.conf

[globals] 
TELEFONISTA=SIP/4024&SIP/4022&SIP/4026 

[general] ;Opções gerais do Dialplan
writeprotect=no ;Modo somente leitura
static=yes ;Modo estático

[ramais]
exten => _XXXX,1,Dial(SIP/${EXTEN},60,tT)

;Fixo Local
exten => _0XX[2-5]XXXXXXX,1,Dial(SIP/tellfree/${EXTEN},30,tT)

;Celular Local
exten => _0XX9[4-9]XXXXXXX,1,Dial(SIP/tellfree/${EXTEN},30,tT)

;Celular Nextel
exten => _0XX7XXXXXXX,1,Dial(SIP/tellfree/${EXTEN},30,tT)

[URA]
exten => s,1,Answer()
exten => s,n,Background(/var/lib/asterisk/sounds/BoasVidas)
exten => s,n,WaitExten(1)
exten => s,n,Dial(${TELEFONISTA},30,tT)

But when I received a call just ring SIP/4024, not others SIP account.

What I do for ring all SIP in the same time?

Thanks!

That is how two devices can be dialed at the same time. What does the console output show when you attempt it?