diff --git a/ChangeLog b/ChangeLog
index 60c48022..44930bed 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+2009-04-04  Nicolas François  <nicolas.francois@centraliens.net>
+
+	* libmisc/isexpired.c: Document the isexpired return value.
+
 2009-04-04  Nicolas François  <nicolas.francois@centraliens.net>
 
 	* libmisc/age.c: Return a specific message when sp_lstchg is null.
diff --git a/libmisc/isexpired.c b/libmisc/isexpired.c
index e93c9d49..728159fb 100644
--- a/libmisc/isexpired.c
+++ b/libmisc/isexpired.c
@@ -51,6 +51,13 @@
  *
  *	isexpired calculates the expiration date based on the
  *	password expiration criteria.
+ *
+ * Return value:
+ *	0: The password is still valid
+ *	1: The password has expired, it must be changed
+ *	2: The password has expired since a long time and the account is
+ *	   now disabled. (password cannot be changed)
+ *	3: The account has expired
  */
 int isexpired (const struct passwd *pw, const struct spwd *sp)
 {