diff --git a/lib/rex.rb b/lib/rex.rb
index cc816210bc..e2037b2548 100644
--- a/lib/rex.rb
+++ b/lib/rex.rb
@@ -35,3 +35,11 @@ require 'rex/socket'
 # Parsers
 require 'rex/parser/arguments'
 require 'rex/parser/ini'
+
+# Overload the Kernel.sleep() function to be thread-safe
+Kernel.class_eval("
+	def sleep (seconds)
+		Rex::ThreadSafe.sleep(seconds)
+	end
+")
+