dmd 2.066.1 cannot build phobos 2.066.1

[Andrei Alexandrescu via Digitalmars-d]

I wonder how this could have happened. Here's what I did:

git clone --quiet -b v2.066.1 --depth=1 
git://github.com/D-Programming-Language/dmd.git dmd-2.066.1

git clone --quiet -b v2.066.1 --depth=1 
git://github.com/D-Programming-Language/druntime.git druntime-2.066.1

git clone --quiet -b v2.066.1 --depth=1 
git://github.com/D-Programming-Language/phobos.git phobos-2.066.1

After this I had three nice directories. Then I built dmd, it worked. 
Then I built druntime making sure I pass DMD=../dmd-2.066.1/src/dmd in 
make's command line. That worked, too.

When I built phobos I got:

====
Error: unrecognized switch '-conf='
====

How did it happen that the -conf= flag is required by phobos 2.066.1 yet 
was not implemented in the same version of dmd?


Thanks,

Andrei