Error: "could not read from statistics collector pipe"

Hello!

In my PostgreSQL logfile, I see that the following entries occur
very frequently:

2006-01-27 10:37:29 FATAL could not read from statistics collector
pipe: No error
2006-01-27 10:37:30 LOG statistics collector process (PID 5940)
was terminated by signal 1

(PostgreSQL 8.1.2, WinXP SP2, Athlon64 X2 3800, 2 GB RAM)

These errors occur every 1-2 minutes when the DB is active. What do
these messages mean and how can I stop them from appearing?

I also noticed that during inserting lots of records, the DB becomes
increasingly slower the more records were inserted. For example, the
first 100000 records take 15 minutes, but records 300000-400000 take
3 hours. Could this be related to the messages above?

I tried to execute ANALYZE every 100000 records, but this did not
seem to help.

Thanks in advance for your help!

- Stephan