Finding equivalent resistance in complex circuit

[agoogler]

In my previous question , situated here, I asked about finding the equivalent resistance of the following circuit :

I got some very good answers and some tips. Now what if the same circuit is modified by adding two more resistors on the free connecting wires like this :

How should I find the equivalent resistance now ?
I probably can't redraw the circuit as mentioned in answers to my previous question since every wire has a resistor on it.

 

[dauto]

That's a Wheatstone bridge. It cannot be solved by either parallel or series methods. You must use Kirchhoff's rules