pgsql-bugs@postgresql.org writes:
> time('now') used to work but it doesn't work anymore in PostgreSQL 7.2.
TIME is a reserved word now, or at least more reserved than it used to
be, because we've added some SQL92 syntax that wasn't supported before.
Try
    "time"('now')
or
    'now'::time
or
    CAST('now' AS time)
In the INSERT command you showed originally, I don't actually believe
that you need any cast at all.
            regards, tom lane