According to our documentation, 'userlocks' were removed in PG 8.2:
http://developer.postgresql.org/pgdocs/postgres/runtime-config-developer.html
trace_userlocks (boolean)If on, emit information about user lock usage. Output is the same asfor trace_locks, only for
userlocks.User locks were removed as of PostgreSQL version 8.2. This optioncurrently has no effect.This parameter is
onlyavailable if the LOCK_DEBUG macro was definedwhen PostgreSQL was compiled.
Should we remove this parameter and the supporting code since pre-8.2 is
now end-of-life?
-- Bruce Momjian <bruce@momjian.us> http://momjian.us EnterpriseDB
http://enterprisedb.com
+ It's impossible for everything to be true. +