diff --git a/sip/regen_makefile.sh b/sip/regen_makefile.sh
index 722620b..caf657c 100755
--- a/sip/regen_makefile.sh
+++ b/sip/regen_makefile.sh
@@ -1,8 +1,27 @@
 #!/bin/sh
 
-FILES="*.ttcn *.ttcnpp TCCConversion.cc TCCInterface.cc UD_PT.cc MNCC_EncDec.cc IPL4asp_PT.cc
-IPL4asp_discovery.cc SDP_EncDec.cc RTP_EncDec.cc IPA_CodecPort_CtrlFunctDef.cc RTP_CodecPort_CtrlFunctDef.cc TELNETasp_PT.cc Native_FunctionDefs.cc SIPmsg_PT.cc *.c "
+FILES="
+	*.c
+	*.ttcn
+	*.ttcnpp
+	IPA_CodecPort_CtrlFunctDef.cc
+	IPL4asp_PT.cc
+	IPL4asp_discovery.cc
+	MNCC_EncDec.cc
+	Native_FunctionDefs.cc
+	RTP_CodecPort_CtrlFunctDef.cc
+	RTP_EncDec.cc
+	SDP_EncDec.cc
+	SIPmsg_PT.cc
+	TCCConversion.cc
+	TCCInterface.cc
+	TELNETasp_PT.cc
+	UD_PT.cc
+"
 
-export CPPFLAGS_TTCN3="-DIPA_EMULATION_CTRL -DRAN_EMULATION_CTRL"
+export CPPFLAGS_TTCN3="
+	-DIPA_EMULATION_CTRL
+	-DRAN_EMULATION_CTRL
+"
 
 ../regen-makefile.sh SIP_Tests.ttcn $FILES