diff --git a/rpm_spec/core-appvm.spec b/rpm_spec/core-appvm.spec
index 0a1b6d3..2dd5c11 100644
--- a/rpm_spec/core-appvm.spec
+++ b/rpm_spec/core-appvm.spec
@@ -32,6 +32,7 @@ Vendor:		Invisible Things Lab
 License:	GPL
 URL:		http://www.qubes-os.org
 Requires:	/usr/bin/xenstore-read
+Requires:   fedora-release = 13
 Provides:   qubes-core-vm
 
 %define _builddir %(pwd)/appvm
diff --git a/rpm_spec/core-netvm.spec b/rpm_spec/core-netvm.spec
index b7d3df5..7fab43e 100644
--- a/rpm_spec/core-netvm.spec
+++ b/rpm_spec/core-netvm.spec
@@ -32,6 +32,7 @@ Vendor:		Invisible Things Lab
 License:	GPL
 URL:		http://www.qubes-os.org
 Requires:	/usr/bin/xenstore-read
+Requires:   fedora-release = 13
 Provides:   qubes-core-vm
 
 %define _builddir %(pwd)/netvm