diff --git a/bsc-nat/regen_makefile.sh b/bsc-nat/regen_makefile.sh
index 3d17cfe..5c25366 100755
--- a/bsc-nat/regen_makefile.sh
+++ b/bsc-nat/regen_makefile.sh
@@ -4,6 +4,6 @@
 
 FILES="*.ttcn *.ttcnpp SCCP_EncDec.cc IPA_CodecPort_CtrlFunctDef.cc IPL4asp_PT.cc IPL4asp_discovery.cc TCCConversion.cc TCCInterface.cc RTP_EncDec.cc SDP_EncDec.cc *.c MGCP_CodecPort_CtrlFunctDef.cc"
 
-export CPPFLAGS_TTCN3="-DIPA_EMULATION_SCCP -DIPA_EMULATION_MGCP"
+export CPPFLAGS_TTCN3="-DIPA_EMULATION_SCCP -DIPA_EMULATION_MGCP -DUSE_MTP3_DISTRIBUTOR"
 
 ../regen-makefile.sh $MAIN $FILES