diff --git a/man/man3/quaternion.3 b/man/man3/quaternion.3
index 941df24..224baea 100644
--- a/man/man3/quaternion.3
+++ b/man/man3/quaternion.3
@@ -150,3 +150,10 @@
 .SH SEE ALSO
 .IR matrix (3),
 .IR qball (3)
+.SH BUGS
+To avoid name conflicts with NetBSD,
+.I qdiv
+is a preprocessor macro defined as 
+.IR p9qdiv ;
+see
+.IR intro (3).