diff --git a/Info.pm b/Info.pm
index 6904b9dd..bb95c60b 100644
--- a/Info.pm
+++ b/Info.pm
@@ -421,6 +421,10 @@ and AN routers.
 
 Subclass for Cisco Catalyst 3550,3540,3560 2/3 switches running IOS.
 
+=item SNMP::Info::Layer3::C4000
+
+This class covers Catalyst 4000s and 4500s.
+
 =item SNMP::Info::Layer3::C6500
 
 This class covers Catalyst 6500s in native mode, hybrid mode.  Catalyst 4000's, 3750's, 2970's
@@ -779,7 +783,8 @@ Algorithm for Subclass Detection:
             Aironet (BR500,AP340,350,1200) -> SNMP::Info::Layer3::Aironet
                      AP4800... All Non IOS
             Catalyst 3550,3548,3560        -> SNMP::Info::Layer3::C3550
-            Catalyst 6500, 4000, 3750      -> SNMP::Info::Layer3::C6500
+            Catalyst 4000,4500             -> SNMP::Info::Layer3::C4000
+            Catalyst 6500, 3750            -> SNMP::Info::Layer3::C6500
             Cisco Generic L3 IOS device    -> SNMP::Info::Layer3::Cisco
             Extreme                        -> SNMP::Info::Layer3::Extreme
             Foundry                        -> SNMP::Info::Layer3::Foundry
@@ -838,14 +843,14 @@ sub device_type {
         return $objtype unless (defined $desc and length($desc));
 
         $objtype = 'SNMP::Info::Layer3::C3550'   if $desc =~ /(C3550|C3560)/ ;
+        $objtype = 'SNMP::Info::Layer3::C4000'   if $desc =~ /Catalyst 4[05]00/;
         $objtype = 'SNMP::Info::Layer3::Foundry' if $desc =~ /foundry/i ;
         # Aironet - older non-IOS
         $objtype = 'SNMP::Info::Layer3::Aironet' if ($desc =~ /Cisco/ and $desc =~ /\D(CAP340|AP340|CAP350|350|1200)\D/) ;
         $objtype = 'SNMP::Info::Layer3::Aironet' if ($desc =~ /Aironet/ and $desc =~ /\D(AP4800)\D/) ;
         $objtype = 'SNMP::Info::Layer3::C6500'   if $desc =~ /(c6sup2|c6sup1)/;
-        # Next two untested. Reported working by DA
+        # Next one untested. Reported working by DA
         $objtype = 'SNMP::Info::Layer3::C6500'   if ($desc =~ /cisco/i and $desc =~ /3750/);
-        $objtype = 'SNMP::Info::Layer3::C6500'   if $desc =~ /Catalyst 4000/;
         $objtype = 'SNMP::Info::Layer3::C6500'   if $desc =~ /s72033_rp/;
         # Extreme Networks
         $objtype = 'SNMP::Info::Layer3::Extreme'  if $desc =~ /Alpine38/;
diff --git a/Info/Layer3/C4000.pm b/Info/Layer3/C4000.pm
new file mode 100644
index 00000000..3e22408d
--- /dev/null
+++ b/Info/Layer3/C4000.pm
@@ -0,0 +1,253 @@
+# SNMP::Info::Layer3::C4000
+# Bill Fenner
+#
+# Copyright (c) 2006 Bill Fenner
+# All rights reserved.
+# 
+# Redistribution and use in source and binary forms, with or without 
+# modification, are permitted provided that the following conditions are met:
+# 
+#     * Redistributions of source code must retain the above copyright notice,
+#       this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above copyright notice,
+#       this list of conditions and the following disclaimer in the documentation
+#       and/or other materials provided with the distribution.
+#     * Neither the name of the Author, nor 
+#       names of its contributors may be used to endorse or promote products 
+#       derived from this software without specific prior written permission.
+# 
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 
+# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 
+# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+# ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+# (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 
+# LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+# ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 
+# SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package SNMP::Info::Layer3::C4000;
+# $Id$
+
+use strict;
+
+use Exporter;
+use SNMP::Info::Layer3;
+use SNMP::Info::CiscoVTP;
+use SNMP::Info::CiscoStack;
+use SNMP::Info::CDP;
+use SNMP::Info::CiscoStats;
+use SNMP::Info::CiscoImage;
+use SNMP::Info::MAU;
+
+use vars qw/$VERSION $DEBUG %GLOBALS %MIBS %FUNCS %MUNGE $INIT/ ;
+$VERSION = 1.0;
+@SNMP::Info::Layer3::C4000::ISA = qw/ SNMP::Info::Layer3 SNMP::Info::CiscoStack SNMP::Info::CiscoVTP 
+                                      SNMP::Info::CiscoStats SNMP::Info::CDP
+                                      SNMP::Info::CiscoImage SNMP::Info::MAU Exporter/;
+@SNMP::Info::Layer3::C4000::EXPORT_OK = qw//;
+
+%MIBS =    (
+            %SNMP::Info::Layer3::MIBS,  
+            %SNMP::Info::CiscoVTP::MIBS,
+            %SNMP::Info::CiscoStack::MIBS,
+            %SNMP::Info::CDP::MIBS,
+            %SNMP::Info::CiscoStats::MIBS,
+            %SNMP::Info::CiscoImage::MIBS,
+            %SNMP::Info::MAU::MIBS,
+            'CISCO-ENVMON-MIB' => 'ciscoEnvMonMIB',
+           );
+
+%GLOBALS = (
+            %SNMP::Info::Layer3::GLOBALS,
+            %SNMP::Info::CiscoVTP::GLOBALS,
+            %SNMP::Info::CiscoStack::GLOBALS,
+            %SNMP::Info::CDP::GLOBALS,
+            %SNMP::Info::CiscoStats::GLOBALS,
+            %SNMP::Info::CiscoImage::GLOBALS,
+            %SNMP::Info::MAU::GLOBALS,
+	    'ps1_type' => 'ciscoEnvMonSupplyStatusDescr.1',
+	    'ps1_status' => 'ciscoEnvMonSupplyState.1',
+	    'ps2_type' => 'ciscoEnvMonSupplyStatusDescr.2',
+	    'ps2_status' => 'ciscoEnvMonSupplyState.2',
+           );
+
+%FUNCS = (
+            %SNMP::Info::Layer3::FUNCS,
+            %SNMP::Info::CiscoVTP::FUNCS,
+            %SNMP::Info::CiscoStack::FUNCS,
+            %SNMP::Info::CDP::FUNCS,
+            %SNMP::Info::CiscoStats::FUNCS,
+            %SNMP::Info::CiscoImage::FUNCS,
+            %SNMP::Info::MAU::FUNCS,
+            'fan_state' => 'ciscoEnvMonFanState',
+            'fan_descr' => 'ciscoEnvMonFanStatusDescr',
+         );
+
+%MUNGE = (
+            %SNMP::Info::Layer3::MUNGE,
+            %SNMP::Info::CiscoVTP::MUNGE,
+            %SNMP::Info::CiscoStack::MUNGE,
+            %SNMP::Info::CDP::MUNGE,
+            %SNMP::Info::CiscoStats::MUNGE,
+            %SNMP::Info::CiscoImage::MUNGE,
+            %SNMP::Info::MAU::MUNGE,
+         );
+
+# use MAU-MIB for admin. duplex
+*SNMP::Info::Layer3::C4000::i_duplex_admin = \&SNMP::Info::MAU::mau_i_duplex_admin;
+
+sub fan {
+    my $c4000 = shift;
+    my $fan_state = $c4000->fan_state();
+    my $fan_descr = $c4000->fan_descr();
+    my $ret = "";
+    my $s = "";
+    foreach my $i (sort {$a <=> $b} keys %$fan_state) {
+	$ret .= $s . $fan_descr->{$i} . ": " . $fan_state->{$i};
+	$s = ", ";
+    }
+    return undef if ($s eq "");
+    $ret;
+}
+
+sub cisco_comm_indexing { 1; }
+
+1;
+__END__
+
+=head1 NAME
+
+SNMP::Info::Layer3::C4000 - Perl5 Interface to Cisco Catalyst 4000 Layer 2/3 Switches running IOS
+
+=head1 AUTHOR
+
+Bill Fenner
+
+=head1 SYNOPSIS
+
+ # Let SNMP::Info determine the correct subclass for you. 
+ my $c4000 = new SNMP::Info(
+                          AutoSpecify => 1,
+                          Debug       => 1,
+                          # These arguments are passed directly on to SNMP::Session
+                          DestHost    => 'myswitch',
+                          Community   => 'public',
+                          Version     => 2
+                        ) 
+    or die "Can't connect to DestHost.\n";
+
+ my $class      = $c4000->class();
+ print "SNMP::Info determined this device to fall under subclass : $class\n";
+
+=head1 DESCRIPTION
+
+Abstraction subclass for Cisco Catalyst 4000 Layer 2/3 Switches.  
+
+These devices run IOS but have some of the same charactersitics as the Catalyst WS-C family (5xxx). 
+For example, forwarding tables are held in VLANs, and extended interface information
+is gleened from CISCO-SWITCH-MIB.
+
+For speed or debugging purposes you can call the subclass directly, but not after determining
+a more specific class using the method above. 
+
+ my $c4000 = new SNMP::Info::Layer3::C4000(...);
+
+=head2 Inherited Classes
+
+=over
+
+=item SNMP::Info::Layer3
+
+=item SNMP::Info::CiscoVTP
+
+=item SNMP::Info::CiscoStack
+
+=item SNMP::Info::CiscoStats
+
+=item SNMP::Info::CDP
+
+=item SNMP::Info::CiscoImage
+
+=back
+
+=head2 Required MIBs
+
+=over
+
+=item Inherited Classes' MIBs
+
+See SNMP::Info::Layer3 for its own MIB requirements.
+
+See SNMP::Info::CiscoVTP for its own MIB requirements.
+
+See SNMP::Info::CiscoStack for its own MIB requirements.
+
+See SNMP::Info::CiscoStats for its own MIB requirements.
+
+See SNMP::Info::CDP for its own MIB requirements.
+
+See SNMP::Info::CiscoImage for its own MIB requirements.
+
+=back
+
+=head1 GLOBALS
+
+These are methods that return scalar value from SNMP
+
+=head2 Globals imported from SNMP::Info::Layer3
+
+See documentation in SNMP::Info::Layer3 for details.
+
+=head2 Global Methods imported from SNMP::Info::CiscoVTP
+
+See documentation in SNMP::Info::CiscoVTP for details.
+
+=head2 Global Methods imported from SNMP::Info::CiscoStack
+
+See documentation in SNMP::Info::CiscoStack for details.
+
+=head2 Globals imported from SNMP::Info::CDP
+
+See documentation in SNMP::Info::CDP for details.
+
+=head2 Globals imported from SNMP::Info::CiscoStats
+
+See documentation in SNMP::Info::CiscoStats for details.
+
+=head2 Globals imported from SNMP::Info::CiscoImage
+
+See documentation in SNMP::Info::CiscoImage for details.
+
+=head1 TABLE ENTRIES
+
+These are methods that return tables of information in the form of a reference
+to a hash.
+
+=head2 Table Methods imported from SNMP::Info::Layer3
+
+See documentation in SNMP::Info::Layer3 for details.
+
+=head2 Table Methods imported from SNMP::Info::CiscoVTP
+
+See documentation in SNMP::Info::CiscoVTP for details.
+
+=head2 Table Methods imported from SNMP::Info::CiscoStack
+
+See documentation in SNMP::Info::CiscoStack for details.
+
+=head2 Table Methods imported from SNMP::Info::CDP
+
+See documentation in SNMP::Info::CDP for details.
+
+=head2 Table Methods imported from SNMP::Info::CiscoStats
+
+See documentation in SNMP::Info::CiscoStats for details.
+
+=head2 Table Methods imported from SNMP::Info::CiscoImage
+
+See documentation in SNMP::Info::CiscoImage for details.
+
+=cut
+