--- loncom/lonnet/perl/lonnet.pm	2014/03/09 15:39:04	1.1252
+++ loncom/lonnet/perl/lonnet.pm	2014/03/25 09:41:08	1.1253
@@ -1,7 +1,7 @@
 # The LearningOnline Network
 # TCP networking package
 #
-# $Id: lonnet.pm,v 1.1252 2014/03/09 15:39:04 raeburn Exp $
+# $Id: lonnet.pm,v 1.1253 2014/03/25 09:41:08 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -890,7 +890,17 @@ sub spareserver {
 }
 
 sub compare_server_load {
-    my ($try_server, $spare_server, $lowest_load) = @_;
+    my ($try_server, $spare_server, $lowest_load, $required) = @_;
+
+    if ($required) {
+        my ($reqdmajor,$reqdminor) = ($required =~ /^(\d+)\.(\d+)$/);
+        my $remoterev = &get_server_loncaparev(undef,$try_server);
+        my ($major,$minor) = ($remoterev =~ /^\'?(\d+)\.(\d+)\.[\w.\-]+\'?$/);
+        if (($major eq '' && $minor eq '') ||
+            (($reqdmajor > $major) || (($reqdmajor == $major) && ($reqdminor > $minor)))) {
+            return ($spare_server,$lowest_load);
+        }
+    }
 
     my $loadans     = &reply('load',    $try_server);
     my $userloadans = &reply('userload',$try_server);
@@ -951,7 +961,7 @@ sub has_user_session {
 # --------- determine least loaded server in a user's domain which allows login
 
 sub choose_server {
-    my ($udom,$checkloginvia) = @_;
+    my ($udom,$checkloginvia,$required) = @_;
     my %domconfhash = &Apache::loncommon::get_domainconf($udom);
     my %servers = &get_servers($udom);
     my $lowest_load = 30000;
@@ -963,14 +973,14 @@ sub choose_server {
             if ($loginvia) {
                 my ($server,$path) = split(/:/,$loginvia);
                 ($login_host, $lowest_load) =
-                    &compare_server_load($server, $login_host, $lowest_load);
+                    &compare_server_load($server, $login_host, $lowest_load, $required);
                 if ($login_host eq $server) {
                     $portal_path = $path;
                     $isredirect = 1;
                 }
             } else {
                 ($login_host, $lowest_load) =
-                    &compare_server_load($lonhost, $login_host, $lowest_load);
+                    &compare_server_load($lonhost, $login_host, $lowest_load, $required);
                 if ($login_host eq $lonhost) {
                     $portal_path = '';
                     $isredirect = ''; 
@@ -978,7 +988,7 @@ sub choose_server {
             }
         } else {
             ($login_host, $lowest_load) =
-                &compare_server_load($lonhost, $login_host, $lowest_load);
+                &compare_server_load($lonhost, $login_host, $lowest_load, $required);
         }
     }
     if ($login_host ne '') {