diff --git a/ChangeLog b/ChangeLog
index 7328c6aa..0462d7f9 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2009-05-18  Nicolas François  <nicolas.francois@centraliens.net>
+
+	* NEWS, src/usermod.c: Check if the user is busy when the user's
+	UID, name or home directory is changed.
+
 2009-05-18  Nicolas François  <nicolas.francois@centraliens.net>
 
 	* src/userdel.c, libmisc/user_busy.c, libmisc/Makefile.am,
diff --git a/NEWS b/NEWS
index ff110f96..f6c74220 100644
--- a/NEWS
+++ b/NEWS
@@ -10,6 +10,9 @@ shadow-4.1.4 -> shadow-4.1.4.1						UNRELEASED
     the user is running some processes.
   * If not on Linux, continue to search for an utmp record, but make sure
     the process recorded in the utmp entry is still running.
+- usermod
+  * Check if the user is busy when the user's UID, name or home directory
+    is changed.
 
 shadow-4.1.3.1 -> shadow-4.1.4						2009-05-10
 
diff --git a/src/usermod.c b/src/usermod.c
index 4c87f153..f178a152 100644
--- a/src/usermod.c
+++ b/src/usermod.c
@@ -1715,6 +1715,18 @@ int main (int argc, char **argv)
 
 	process_flags (argc, argv);
 
+	/*
+	 * The home directory, the username and the user's UID should not
+	 * be changed while the user is logged in.
+	 */
+	if (   (uflg || lflg || dflg)
+	    && (user_busy (user_name, user_id) != 0)) {
+		fprintf (stderr,
+		         _("%s: user %s is currently logged in\n"),
+		         Prog, user_name);
+		exit (E_USER_BUSY);
+	}
+
 #ifdef ACCT_TOOLS_SETUID
 #ifdef USE_PAM
 	{