diff --git a/ndpi.spec b/ndpi.spec
index 2bd69e9..6d3937e 100644
--- a/ndpi.spec
+++ b/ndpi.spec
@@ -96,6 +96,8 @@ This package contains the ndpiReader binary.
 %package -n ndpi-common
 Summary:        Common files used by nDPI
 Group:          Development/Libraries/C and C++
+# version 3 rpm did not yet follow rules correctly
+Conflicts:      libndpi3
 
 %description -n ndpi-common
 nDPI is a ntop-maintained superset of the OpenDPI library. It extends