Ned - 

>> For the record, I've had that happening too intermittently on a
>> debian server. I have never been able to nail it down (or reproduce
>> it consistently), but it looked like some previous UUID generator
>> was locking up /dev/urandom. Simple 'cat'-ing /dev/urandom used to
>> cure the situation, as did an ugly variety of workarounds...

> I believe that what was happening may have been that the UTF-8 text
> converter attached to the stream may have been trying to interpret
> the bytes.

This might well fix the bug that started this thread, but if so, mine
was different. The UUID generator bug I am describing has been
happening for the last couple of years, well before the UTF stuff.
The scenario was always that all 4 bytes read from /dev/urandom
appeared as nil, which caused a walkback. (As I said, cat/more/etc. on
/dev/urandom unblocked it).

The issue is moot however: since I the server has migrated, I haven't
seen it happen (but I haven't had a rush of UUID creation either).

Michal