There was a post recently on using Syslog with PostgreSQL on pgsql-general. As you can see, Tom Lane kindly replied in the thread.
I decided that it might be a good idea to submit a DOC patch. I only received on comment on the patch, so I don't know if it will be applied or not. The comment, caused me to consider creating a table for the docs that correlated the different log levels between PostgreSQL, Syslog and Eventlog. The HTML version of that table is below:
Log level correlation
PostgreSQL
Syslog
Eventlog
DEBUG1-DEBUG5
LOG_DEBUG
EVENTLOG_INFORMATION_TYPE
LOG
LOG_INFO
EVENTLOG_INFORMATION_TYPE
INFO
LOG_INFO
EVENTLOG_INFORMATION_TYPE
NOTICE
LOG_NOTICE
EVENTLOG_INFORMATION_TYPE
WARNING
LOG_NOTICE
EVENTLOG_WARNING_TYPE
ERROR
LOG_WARNING
EVENTLOG_ERROR_TYPE
FATAL
LOG_ERR
EVENTLOG_ERROR_TYPE
PANIC
LOG_CRIT
EVENTLOG_ERROR_TYPE
I have decided not to submit a patch to -docs for this. I do not have the inclination to use DocBook SGML (XML sure and yes it is quite a bit different) and since we are past year 2001, the tools out there I could find support only DocBook XML.