diff --git a/asn1/h225/Makefile b/asn1/h225/Makefile
index 3fb078917a..5f580777b5 100755
--- a/asn1/h225/Makefile
+++ b/asn1/h225/Makefile
@@ -1,6 +1,16 @@
 # $Id$
 
-../../epan/dissectors/packet-h225.c : ../../tools/asn2eth.py h225.asn packet-h225-template.c packet-h225-template.h h225.cnf 
-	python ../../tools/asn2eth.py -X -e -p h225 -c h225.cnf -s packet-h225-template h225.asn
-	cp packet-h225.* ../../epan/dissectors
+DISSECTOR_FILES=packet-h225.c packet-h225.h
 
+all: generate_dissector
+
+generate_dissector: $(DISSECTOR_FILES)
+
+$(DISSECTOR_FILES): ../../tools/asn2eth.py h225.asn packet-h225-template.c packet-h225-template.h h225.cnf 
+	python ../../tools/asn2eth.py -X -e -p h225 -c h225.cnf -s packet-h225-template h225.asn
+
+clean:
+	rm -f parsetab.py $(DISSECTOR_FILES)
+
+copy_files: generate_dissector
+	cp $(DISSECTOR_FILES) ../../epan/dissectors