[sr-dev] Compilation ignoring directory settings

I compile and install with: # make prefix=/ mandir=/usr/local/man cfg_dir=/etc/sip-router install

then I run: # ser

and got: ERROR: loading config file(/usr/local/etc/ser/ser.cfg): No such file or directory

The ERROR message is expected (there is no /usr/local/etc/ser directory at all), but why is sip-router (ser) trying to find configuration file on the default directory if I explicitly compile it pointing to another one? From what I looked on Makefile.defs the config directory is gived by the "cfg_dir" variable... "prefix" is honor, since "ser" binary is installed correctly:

# which ser /sbin/ser

Edson.