I've never done this before but your article did give me an idea. What if you were to short CW. and buy Vod?
If the deal goes through CW. goes up and you lose out on 10% or, but Vod should go up as well as I think the deal would be a very good price for them, and I think it is a great company and so you may lose out on that short term trade but the risk is limited.
If the deal doesn't go through then the short on CW. should pay out nicely, and you will see a drop in Vod but not too much.