Here is the outcome of my latest experiment conducted by 'Dr. Benz'
Shift your fingers up by one fret each while playing the chord Em whose result will be your middle finger goes upto fret-2, string-6 and your ring finger goes upto fret 2, string 5.Strike the fifth and sixth string continuosly and QUICKLY(REALLY FAST) and keeping up the striking without stopping move your ring finger down by one fret and after a while move the middle finger down by one fret to bring it to the Em formation.
U can also start by shifting your finger downwards.
Try it out and reply.