diff --git a/pisi-spec.rng b/pisi-spec.rng
index 9b204c8d..4950caa8 100644
--- a/pisi-spec.rng
+++ b/pisi-spec.rng
@@ -391,6 +391,7 @@
                 <value>MonkeysAudio</value>
                 <value>Moria</value>
                 <value>Mozart</value>
+                <value>NCSA</value>
                 <value>NCSA-HDF</value>
                 <value>NEWLIB</value>
                 <value>NPL-1.1</value>