diff --git a/jflex-bootstrap.changes b/jflex-bootstrap.changes
index 05b1760..26a7c70 100644
--- a/jflex-bootstrap.changes
+++ b/jflex-bootstrap.changes
@@ -1,3 +1,8 @@
+-------------------------------------------------------------------
+Mon Dec  2 12:44:30 UTC 2013 - mvyskocil@suse.com
+
+- conflicts with non-bootstrap variant
+
 -------------------------------------------------------------------
 Thu Nov 14 12:31:24 UTC 2013 - mvyskocil@suse.com
 
diff --git a/jflex.changes b/jflex.changes
index 05b1760..6570508 100644
--- a/jflex.changes
+++ b/jflex.changes
@@ -1,3 +1,8 @@
+-------------------------------------------------------------------
+Mon Dec  2 12:44:19 UTC 2013 - mvyskocil@suse.com
+
+- conflicts with bootstrap variant
+
 -------------------------------------------------------------------
 Thu Nov 14 12:31:24 UTC 2013 - mvyskocil@suse.com
 
diff --git a/jflex.spec b/jflex.spec
index 8701913..309f5fe 100644
--- a/jflex.spec
+++ b/jflex.spec
@@ -51,6 +51,9 @@ BuildRequires:  java-cup-bootstrap
 %if %without bootstrap
 BuildRequires:  jflex-bootstrap
 BuildRequires:  junit
+Conflicts:      jflex-bootstrap
+%else
+Conflicts:      jflex
 %endif
 BuildRequires:  java-1_5_0-gcj-compat-devel
 BuildArch:      noarch