I had this too when I got my powerbook last week, I picked it up from an apple store in the uk. I dont know for sure now how long it lasted for but for the first two days at least I had the "tingle" you mention. One thing that may interest you though, when I got back home to Prague, I plugged in the powerbook adapter to an extension cable in my flat, and the fuses blew. I had to go down into the basement and reset the fuses when I came back up I checked out the adapter and it smelt like something had burnt inside, I havent been able to get into it yet to check. I bought a new adapter which is working fine and it was only today after reading your post that I noticed that I dont have that tingly feeling anymore.
Short version - It might just be the adapter, when I was in the UK I bought the european plugs etc too, and we use the same voltage as the UK.
Joolz