I'm running Apache 2.2, PHP 5.2, and Postgres 8.2 on Windows, and I'm seeing something funky in Apache's error.log file. Occasionally, I'll see the message "row number -1 is out of range 0..-1" pop up over and over. Unlike all the other lines in that log file, there's no timestamp or log level. Just that exact string.

Googling around, it appears that message is, character for character, a common Postgres error message, but is not an Apache error. I've seen it happen multiple times, and on several different servers. I can't seem to reproduce it, though. I've tried throwing all sorts of error ridden database queries and result set inquiries at Postgres via PHP, and none of them seem to trigger that line being written to the log file. Is it possible for Postgres errors to be ending up in my Apache log file, and if so, how? What would trigger an error message like that?

Thanks!