running mongod always shows WARNING messages about "fastsync"

When I run mongod, following warning messages appears.

=============================================
warning "fastsync" should not be put in your configuration file
=============================================

This will happen even if I comment out "fastsync" setting from config file.
If I delete it rather than comment out, WARNING dissapeared.

Does this come from the changes about cmdline.cpp described in the following url?
https://github.com/dannenberg/mongo/commit/b358be1cb095888b47fa89e4c010d12e8af16794