Mine

[incoming]
include => tihevent
exten => 8301048,1,Answer
exten => 8301048,2,Goto(outgoing,s,1)

[outgoing]
include => tihevent
exten => s,1,Wait(2)
exten => s,n,Set(TIMEOUT(digit)=20)
exten => s,n,Set(TIMEOUT(response)=20)
exten => s,n,Background(to-extension)

exten => _1NXXNXXXXXX,1,Dial(SIP/melpi/${EXTEN:1},120,tr)

[tihevent]
exten => h,1,Hangup     ;hangup event
exten => i,1,Hangup     ;invalid event
exten => t,1,Hangup     ;timeout even

    -- Executing Answer("SIP/92218301048-6db2", "") in new stack
    -- Executing Goto("SIP/92218301048-6db2", "outgoing|s|1") in new stack
    -- Goto (superphonepk-out,s,1)
    -- Executing Wait("SIP/92218301048-6db2", "2") in new stack
    -- Executing Set("SIP/92218301048-6db2", "TIMEOUT(digit)=20") in new stack
    -- Digit timeout set to 20
    -- Executing Set("SIP/92218301048-6db2", "TIMEOUT(response)=20") in new stack
    -- Response timeout set to 20
    -- Executing BackGround("SIP/92218301048-6db2", "to-extension") in new stack
    -- Playing 'to-extension' (language 'en')
    -- Invalid extension '7' in context 'outgoing' on SIP/92218301048-6db2
  == CDR updated on SIP/92218301048-6db2
    -- Executing Hangup("SIP/92218301048-6db2", "") in new stack
  == Spawn extension (outgoing, i, 1) exited non-zero on 'SIP/92218301048-6db2'
    -- Executing Hangup("SIP/92218301048-6db2", "") in new stack
  == Spawn extension (outgoing, h, 1) exited non-zero on 'SIP/92218301048-6db2'