6.3.2.6. DPRE 
If the parameter DPRE is set, the dialing information that was actually
transmitted (including, for example, prefix digits, AMO LODR, OUTPULSE)
is passed along to the call detail recording function.
More information you can find in section "INCDR - Feature Usage
Examples and COT Parameters, Chapter
268, "DPRE - Send dial information actually sent to partner system
as destination number with prefix digits to call data recording".