Could not open log file "pg_log/postgresql-Sun.log": No such file or directory

Question

After installing postgresql on fedora 17 using the yum package manager. When I try to start it I get the error message.

[vagrant@example ~]$ sudo /sbin/service postgresql status
Redirecting to /bin/systemctl status  postgresql.service
postgresql.service - PostgreSQL database server
      Loaded: loaded (/usr/lib/systemd/system/postgresql.service; disabled)
      Active: failed (Result: exit-code) since Sun, 09 Jun 2013 07:01:16 -0700; 5s ago
     Process: 19068 ExecStart=/usr/bin/pg_ctl start -D ${PGDATA} -s -o -p ${PGPORT} -w -t 300 (code=exited, status=1/FAILURE)
     Process: 19062 ExecStartPre=/usr/bin/postgresql-check-db-dir ${PGDATA} (code=exited, status=0/SUCCESS)
      CGroup: name=systemd:/system/postgresql.service

Jun 09 07:01:11 example.vagrant.com pg_ctl[19068]: FATAL:  could not open log file "pg_log/postgresql-Sun.log": No such file or directory
Jun 09 07:01:16 example.vagrant.com pg_ctl[19068]: pg_ctl: could not start server
Jun 09 07:01:16 example.vagrant.com pg_ctl[19068]: Examine the log output.

I'm curious why a pg_log directory is just not created on the postgres installation.