I'm not a lawyer, so I may be mistaken, but here is what I don't get with the whole Tzipi Livni arrest issue. It's being treated like it's primarily an Israeli problem, with a vague mention of it possibly affecting some other foreign nations. But no one seems to take notice that this loophole can be used to arrest retired members of the British Government - or even, currently active members of the government. I don't suppose they have diplomatic immunity in their own country.
Someone needs to get an anti-Iraqi-War group (which isn't also anti-Israeli) to convince a "local" magistrate to issue an arrest warrant for a prominent member of the UK government. This will highlight the flaw in the system and it's relevance to the wider British population, and the issue will be sorted out quicker than it takes to get Milchig.