courier-0.50.1 install troubles

[Marat Bakeev]

I`ve upgraded my old courier to new version in ports, it installed 
authdaemon as a dependency. in make config i checked MySQL auth options, but 
after install logs said that authmysql cannot be loaded.
I`ve had to manually copy libauthmysql.so from authlib port work directory 
to the /usr/local/lib & copy authmysql.rc from /usr/local/etc/courier to 
/usr/local/etc/authlib
why the port cannot copy .so file by itself?