Were you a member of any team before? Did you recently browse teams whilst signed in?

How this can happen [a first I've heard of] I don't know, so cant tell you how to avoid this, but looking at the subject team page http://www.worldcommunitygrid.org/team/viewTeamInfo.do?teamId=33JH13V1TT1 it's easy enough to accidentally hit the "Join this team" button. Really don't know what happens after hitting the button... whether it requires a confirmation, but vaguely recollect that if you were a member of a team before it would retire you of that one at the same time.

edit: It's something WCG techs could trace, IP, time of action etc. If not a member of a team and you have a weak password... but that would be unheard of. What would anyone stand to gain but embarrass a team infinitely? (Whilst, *someone* at some point was hijacking captainless teams and giving them a different country link. It's weird to see a team change from representing one country to move to another.)

Check at GPUGrid what the team state is for you. There's a BOINC global team feature, and WCG being on new server 700 [since March], something buggy(?) could have remotely kicked this. No idea if WCG has this enabled. At BOINCStats your listed as being part of that team: http://boincstats.com/en/stats/search/#Jim1348

The BOINCstats site does not work for me at all under firefox since their revamp. In IE can see that you're only member of that team at WCG.