Index: sources/src/Makefile
===================================================================
--- sources/src/Makefile	(revision 3)
+++ sources/src/Makefile	(revision 4)
@@ -10,8 +10,4 @@
 # |                                                             |
 # \------------------------------------------------------------*/
-ifndef SYSTEMC
-$(error SYSTEMC is not defined. This variable should be set to SystemCASS \
-directory when SYSTEMCASS variable is not set.)
-endif
 ifndef SYSTEMCASS
 $(error SYSTEMCASS is not defined. This variable has to be defined to install \
@@ -186,4 +182,5 @@
 
 EXTERNAL_INCLUDES = \
+              ${SYSTEMCASS_INCLUDEDIR}/systemc \
               ${SYSTEMCASS_INCLUDEDIR}/systemc.h \
               ${SYSTEMCASS_INCLUDEDIR}/sc_fwd.h\
@@ -289,4 +286,7 @@
 	cp $*.h ${SYSTEMCASS_INCLUDEDIR}/$*.h
 
+${SYSTEMCASS_INCLUDEDIR}/systemc: systemc
+	cp $< $@
+
 ${SYSTEMCASS_DOCDIR}/%.pdf: %.pdf
 	cp $*.pdf ${SYSTEMCASS_DOCDIR}/$*.pdf
@@ -348,5 +348,5 @@
 	./guess_endianness.x > ${SYSTEMCASS_INCLUDEDIR}/endianness.h
 
-include Makefile.deps
+-include Makefile.deps
 
 ##################
@@ -374,5 +374,5 @@
 #### CLEANING
 clean :
-	echo > Makefile.deps
+	rm -f Makefile.deps
 	rm -f *~
 	rm -f $(OBJECTS)