microsecond log timestamps

Someone probably had a good reason for doing this, but looking at
backend/utils/error/elog.c line 592 in 7.1, it looks like the pre-7.1
capability for microsecond timestamp granularity (e.g.,
20010511.14:23:49.325) in tprintf_timestamp() was removed in favor of a
coarser 1-second resolution using time_t in print_timestamp()? Is that
correct? If not, what am I missing?

If so, is anyone aware of an existing patch to give sub-second log
timestamp capability? Microsecond granularity has been very helpful for
query timing.

Regards,
Ed Loehr