Berlin Zoo has two seperate groups of Sumatran Orang-utan, around 9 animals total I believe - strangley though the information board they have up states that "orang-utans come from Borneo" and also they have BOS material around.
I would be really pleased to see more Sumatrans in the UK and hopefully some sort of education/funding relating to the sumatran species - having spent the summer in Sumatra/Bornea you can really see the difference in support between the species, the critically endangered sumatran orang "rehab" centre was basically a hut, a couple of horrible looking cages and a feeding platform - whereas both of the centres I visited in Borneo were on a much larger scale with much better funding and facilities, it seems that it is always BOS that is the group that gets supported by the Zoo community, would be really amazing to see some kind of link between this new project and genuine in situ conservation in Sumatra before the last few animals are exterminated. I guess the problem is making sure the money does what is needed and not just end up in the pocket of some corrupt Indonesian official.