;
; ----------- ( using asterisk 1.4.7 ) ---------------
;
; v_Today will approx number of days since THE epoch (not unix epoch)
; v_today = days + ( months * 30 ) + ( years * 365 )
;
 exten => s,1,Set(v_years=${CDR(start):0:4})               ;   2007-07-13 09:18:11
 exten => s,n,Set(v_months=${CDR(start):5:2})
 exten => s,n,Set(v_days=${CDR(start):8:2})
;
; NO spaces on either side of return type (int in this case), or you'll be scratching your head
;
; repeat - no SPACE between int and | or )
;
 exten => s,n,Set(v_Today=${MATH( ${v_days}  + ${MATH( ${v_months} *  30 |int)} |int)})
 exten => s,n,Set(v_Today=${MATH( ${v_Today} + ${MATH( ${v_years}  * 365 |int)} |int)})
;
 exten => s,n,NoOp(${v_years})
 exten => s,n,NoOp(${v_months})
 exten => s,n,NoOp(${v_days})
 exten => s,n,NoOp(${v_Today})
 exten => s,n,Hangup()
;
; ------------------------------------

Sometime ago it was decided to go in the direction of using '|' (pipe character) as the argument separator for
applications/functions in asterisk.

 I've noticed while playing with the MATH function in asterisk 1.4.0Beta2 that the function does NOT work
correctly if you use a comma as the argument separator.
 The technical reason for this is that the macro used to parse the arguments in app.h is actually 
hardcoded to a pipe character.
 The result for the MATH function is that the return_type argument is ignored, the math you're attempting 
is correctly computed and always returned as a float.

 Hope that helps anyone scratching their head.