diff --git a/lib/rex/post/meterpreter/ui/console/command_dispatcher/core.rb b/lib/rex/post/meterpreter/ui/console/command_dispatcher/core.rb
index 88762dc605..09a63403e9 100644
--- a/lib/rex/post/meterpreter/ui/console/command_dispatcher/core.rb
+++ b/lib/rex/post/meterpreter/ui/console/command_dispatcher/core.rb
@@ -1,4 +1,5 @@
 # -*- coding: binary -*-
+require 'set'
 require 'rex/post/meterpreter'
 require 'rex/parser/arguments'
 
@@ -416,17 +417,17 @@ class Console::CommandDispatcher::Core
     @@load_opts.parse(args) { |opt, idx, val|
       case opt
       when "-l"
-        exts = []
+        exts = SortedSet.new
         msf_path = MeterpreterBinaries.metasploit_data_dir
         gem_path = MeterpreterBinaries.local_dir
         [msf_path, gem_path].each do |path|
           ::Dir.entries(path).each { |f|
             if (::File.file?(::File.join(path, f)) && f =~ /ext_server_(.*)\.#{client.binary_suffix}/ )
-              exts.push($1) unless exts.include?($1)
+              exts.add($1)
             end
           }
         end
-        print(exts.sort.join("\n") + "\n")
+        print(exts.to_a.join("\n") + "\n")
 
         return true
       when "-h"
@@ -464,19 +465,19 @@ class Console::CommandDispatcher::Core
   end
 
   def cmd_load_tabs(str, words)
-    tabs = []
+    tabs = SortedSet.new
     msf_path = MeterpreterBinaries.metasploit_data_dir
     gem_path = MeterpreterBinaries.local_dir
     [msf_path, gem_path].each do |path|
     ::Dir.entries(path).each { |f|
       if (::File.file?(::File.join(path, f)) && f =~ /ext_server_(.*)\.#{client.binary_suffix}/ )
         if (not extensions.include?($1))
-          tabs.push($1) unless tabs.include?($1)
+          tabs.add($1)
         end
       end
     }
     end
-    return tabs
+    return tabs.to_a
   end
 
   def cmd_use(*args)