--- loncom/lonnet/perl/lonnet.pm	2009/03/09 05:25:44	1.990
+++ loncom/lonnet/perl/lonnet.pm	2009/04/11 14:47:51	1.993
@@ -1,7 +1,7 @@
 # The LearningOnline Network
 # TCP networking package
 #
-# $Id: lonnet.pm,v 1.990 2009/03/09 05:25:44 raeburn Exp $
+# $Id: lonnet.pm,v 1.993 2009/04/11 14:47:51 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -74,9 +74,7 @@ use strict;
 use LWP::UserAgent();
 use HTTP::Date;
 use Image::Magick;
-use IO::Socket;
 
-# use Date::Parse;
 use vars qw(%perlvar %spareid %pr %prp $memcache %packagetab $tmpdir
             $_64bit %env %protocol);
 
@@ -198,6 +196,33 @@ sub get_server_timezone {
     }
 }
 
+sub get_server_loncaparev {
+    my ($dom,$lonhost) = @_;
+    if (defined($lonhost)) {
+        if (!defined(&hostname($lonhost))) {
+            undef($lonhost);
+        }
+    }
+    if (!defined($lonhost)) {
+        if (defined(&domain($dom,'primary'))) {
+            $lonhost=&domain($dom,'primary');
+            if ($lonhost eq 'no_host') {
+                undef($lonhost);
+            }
+        }
+    }
+    if (defined($lonhost)) {
+        my $cachetime = 24*3600;
+        my ($loncaparev,$cached)=&is_cached_new('serverloncaparev',$lonhost);
+        if (defined($cached)) {
+            return $loncaparev;
+        } else {
+            my $loncaparev = &reply('serverloncaparev',$lonhost);
+            return &do_cache_new('serverloncaparev',$lonhost,$loncaparev,$cachetime);
+        }
+    }
+}
+
 # -------------------------------------------------- Non-critical communication
 sub subreply {
     my ($cmd,$server)=@_;
@@ -9048,23 +9073,31 @@ sub get_dns {
 
 	return %iphost;
     }
-}
 
-#
-#  Given a DNS returns the loncapa host name for that DNS 
-# 
-sub host_from_dns {
-    my ($dns) = @_;
-    my @hosts;
-    my $ip;
-
-    $ip = gethostbyname($dns);	# Initial translation to IP is in net order.
-    if (length($ip) == 4) { 
-	$ip   = &IO::Socket::inet_ntoa($ip);
-	@hosts = get_hosts_from_ip($ip);
-	return $hosts[0];
+    #
+    #  Given a DNS returns the loncapa host name for that DNS 
+    # 
+    sub host_from_dns {
+        my ($dns) = @_;
+        my @hosts;
+        my $ip;
+
+        if (exists($name_to_ip{$dns})) {
+            $ip = $name_to_ip{$dns};
+        }
+        if (!$ip) {
+            $ip = gethostbyname($dns); # Initial translation to IP is in net order.
+            if (length($ip) == 4) { 
+	        $ip   = &IO::Socket::inet_ntoa($ip);
+            }
+        }
+        if ($ip) {
+	    @hosts = get_hosts_from_ip($ip);
+	    return $hosts[0];
+        }
+        return undef;
     }
-    return undef;
+
 }
 
 BEGIN {