diff --git a/java_cup.spec b/java_cup.spec
index 7a5f596..c5b87cf 100644
--- a/java_cup.spec
+++ b/java_cup.spec
@@ -20,6 +20,8 @@ Buildarch:	noarch
 Buildroot:	%{_tmppath}/%{name}-%{version}-buildroot
 #Distribution:	JPackage
 #Vendor:		JPackage Project
+# RHEL3 and FC2
+Obsoletes:	cup <= 0:v10k
 
 %description
 java_cup is a LALR Parser Generator for Java