Mott Leroy <mott(at)acadaca(dot)com> writes:
> How can I go about tracking down the source of these?
I think if you turn on log_connections, you'll at least get log entries
showing what machine(s) the bad connection attempts are coming from.
Not sure if that'll be enough for you.
> My db clients are JDBC connections from web applications.
You might try asking about it on the pgsql-jdbc list; perhaps there's a
known issue of this kind.
regards, tom lane