--- loncom/lti/ltiutils.pm	2019/07/18 18:28:46	1.17
+++ loncom/lti/ltiutils.pm	2022/03/29 20:12:46	1.18
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # Utility functions for managing LON-CAPA LTI interactions 
 #
-# $Id: ltiutils.pm,v 1.17 2019/07/18 18:28:46 raeburn Exp $
+# $Id: ltiutils.pm,v 1.18 2022/03/29 20:12:46 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -32,6 +32,7 @@ use strict;
 use Net::OAuth;
 use Digest::SHA;
 use Digest::MD5 qw(md5_hex);
+use Encode;
 use UUID::Tiny ':std';
 use Apache::lonnet;
 use Apache::loncommon;
@@ -821,7 +822,7 @@ END
 sub setup_logout_callback {
     my ($uname,$udom,$server,$ckey,$secret,$service_url,$idsdir,$protocol,$hostname) = @_;
     if ($service_url =~ m{^https?://[^/]+/}) {
-        my $digest_user = &Encode::decode_utf8($uname.':'.$udom);
+        my $digest_user = &Encode::decode('UTF-8',$uname.':'.$udom);
         my $loginfile = &Digest::SHA::sha1_hex($digest_user).&md5_hex(&md5_hex(time.{}.rand().$$));
         if ((-d $idsdir) && (open(my $fh,'>',"$idsdir/$loginfile"))) {
             print $fh "$uname,$udom,$server\n";