Empty postgres.pid file is still existing in gear after stop

https://bugzilla.redhat.com/show_bug.cgi?id=1080822 Create one app(e.g.,
myphp53), embedded with postgresql-8.4/9.2, stop postgresql db cartridge,
found postgresql/pid/postgres.pid still existing in rhcsh and even though
prompts "Stopping postgresql-8.4 ... done"