diff --git a/src/engine/Makefile b/src/engine/Makefile
index 1d241879c3..752b9365f5 100644
--- a/src/engine/Makefile
+++ b/src/engine/Makefile
@@ -58,7 +58,7 @@ $(TARGET): $(OBJS)
 	$(CC) -c $(CFLAGS) $(INCLPATH) $<
 
 swig:
-	swig -I. --guile swig.i
+	swig -I. -guile swig.i
 
 
 depend:
diff --git a/src/engine/Makefile.in b/src/engine/Makefile.in
index 29005f2424..6d8a0841aa 100644
--- a/src/engine/Makefile.in
+++ b/src/engine/Makefile.in
@@ -58,7 +58,7 @@ $(TARGET): $(OBJS)
 	$(CC) -c $(CFLAGS) $(INCLPATH) $<
 
 swig:
-	swig -I. --guile swig.i
+	swig -I. -guile swig.i
 
 
 depend: