--- a/gsoap/src/Makefile.am
+++ b/gsoap/src/Makefile.am
@@ -10,11 +10,13 @@ AUTOMAKE_OPTIONS = foreign 1.4
 AM_YFLAGS=-d -v
 AM_LFLAGS=$(LEX_FLAGS)
 
+BUILT_SOURCES = soapcpp2_yacc.h
+
 bin_PROGRAMS=soapcpp2
 
 soapcpp2_CFLAGS=$(BISON_DEFINE) $(LEX_DEFINE) $(C_DEBUG_FLAGS) $(SOAPCPP2_IMPORTPATH) -D$(platform)
 soapcpp2_LDADD=$(YACC_LIB) $(LEXLIB)
-soapcpp2_SOURCES= soapcpp2_yacc.y soapcpp2_yacc.h soapcpp2_lex.l symbol2.c error2.c init2.c soapcpp2.c
+soapcpp2_SOURCES= soapcpp2_yacc.y soapcpp2_lex.l symbol2.c error2.c init2.c soapcpp2.c
 
 CLEANFILES= *~ soapcpp2_lex.c soapcpp2_yacc.c soapcpp2_yacc.h soapcpp2_yacc.output