--- loncom/interface/loncommon.pm	2007/05/29 17:48:44	1.536
+++ loncom/interface/loncommon.pm	2007/06/18 23:19:12	1.537
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # a pile of common routines
 #
-# $Id: loncommon.pm,v 1.536 2007/05/29 17:48:44 raeburn Exp $
+# $Id: loncommon.pm,v 1.537 2007/06/18 23:19:12 albertel Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -2054,6 +2054,7 @@ if $first is set to 'lastname' then it r
 ###############################################################
 sub plainname {
     my ($uname,$udom,$first)=@_;
+    return if (!defined($uname) || !defined($udom));
     my %names=&getnames($uname,$udom);
     my $name=&Apache::lonnet::format_name($names{'firstname'},
 					  $names{'middlename'},
@@ -2085,6 +2086,7 @@ if the user does not
 
 sub nickname {
     my ($uname,$udom)=@_;
+    return if (!defined($uname) || !defined($udom));
     my %names=&getnames($uname,$udom);
     my $name=$names{'nickname'};
     if ($name) {
@@ -2100,6 +2102,7 @@ sub nickname {
 
 sub getnames {
     my ($uname,$udom)=@_;
+    return if (!defined($uname) || !defined($udom));
     if ($udom eq 'public' && $uname eq 'public') {
 	return ('lastname' => &mt('Public'));
     }