Darn—looks as if the AC adaptor for my PDA has a Wackelkontakt[*].
I noticed this when we were in the temple; connecting it to the PDA would sometimes make the charging light go on, sometimes not. Jiggling the short cord from the socket to the adaptor would make ominous buzzing noises and would sometimes work, but I was never sure how long the connection would hold.
If this stays this way, I'm not sure what to do. I don't know whether these things can be repaired easily by an electrician (the adaptors are probably not designed to be opened or serviced) or whether I'll need to buy a new one.
[*] What's this in English? I'm referring to an electrical connection that is not reliably made. Either it'll make and break itself randomly, or (as in this case) the connection will be there only if the two components are aligned fairly carefully: jiggling the cable will cause the connection to make or break and it's difficult to maintain the connection because you're not sure whether jarring it or gravity or other influences will cause the connectors to move into a "bad" position.
LEO suggests "insulate contact", "loose connection", "loose contact", and "slack joint", but I don't think I've ever heard any of them.