[default]
exten => 123,1,Macro(say-digits,3000)
exten => 123,2,Macro(say-digits,5055551212)
exten => 123,3,Macro(say-digits,98005551212)

[macro-say-digits]
;
; ARG1=number to say
;
exten => s,1,GotoIf($[${LEN(${ARG1})} != 10]?s,3)
exten => s,2,SayDigits(${ARG1:0:3})
exten => s,3,GotoIf($[${LEN(${ARG1})} != 10]?s,6)
exten => s,4,Wait(.25)
exten => s,5,SayDigits(${ARG1:3:3})
exten => s,6,GotoIf($[${LEN(${ARG1})} != 10]?s,10)
exten => s,7,Wait(.25)
exten => s,8,SayDigits(${ARG1:6})
exten => s,9,Goto(s,12)
exten => s,10,Wait(.25)
exten => s,11,SayDigits(${ARG1})
exten => s,12,NoOp