diff --git a/lib/gelf/notifier.rb b/lib/gelf/notifier.rb
index fcaf0de..7635d4f 100644
--- a/lib/gelf/notifier.rb
+++ b/lib/gelf/notifier.rb
@@ -3,11 +3,21 @@
 require 'gelf/transport/tcp_tls'
 
 # replace JSON and #to_json with Yajl if available
+$yajlavail = false
 begin
-  require 'yajl/json_gem'
+  require 'yajl'
+  $yajlavail = true
 rescue LoadError
 end
 
+def json_dump(obj)
+  if $yajlavail
+    Yajl.dump(obj)
+  else
+    JSON.dump(obj)
+  end
+end
+
 module GELF
   # Graylog2 notifier.
   class Notifier
@@ -163,7 +173,7 @@ def notify_with_level!(message_level, *args)
       if hash['level'] >= level
         if default_options['protocol'] == GELF::Protocol::TCP
           validate_hash(hash)
-          @sender.send(hash.to_json + "\0")
+          @sender.send(json_dump(hash) + "\0")
         else
           @sender.send_datagrams(datagrams_from_hash(hash))
         end
@@ -260,7 +270,7 @@ def validate_hash(hash)
     def serialize_hash(hash)
       validate_hash(hash)
 
-      Zlib::Deflate.deflate(hash.to_json).bytes
+      Zlib::Deflate.deflate(json_dump(hash)).bytes
     end
 
     def self.stringify_keys(data)