Fixes #173. Handle mixed-case header lookups better

git-svn-id: file:///home/svn/framework3/trunk@5271 4d416f70-5f16-0410-b530-b9f4589650da

lib/rex/proto/http/header.rb

@@ -58,12 +58,17 @@ class Packet::Header < Hash
 	#
 	def [](key)
 		begin
-			if ((rv = self.fetch(key)) == nil)
-				rv = self.dcase_hash[key.downcase]	
-			end
+			rv = self.fetch(key)
 		rescue IndexError
 			rv = nil
 		end
+		if (rv == nil)
+			begin
+				rv = self.dcase_hash[key.downcase]	
+			rescue IndexError
+				rv = nil
+			end
+		end
 
 		return rv
 	end