halacha - Can someone trying to convert have mezuzahs on his doorposts?

When one is going through an orthodox conversion, one is asked to keep all the mitzvoth with the exception of fully keeping the shabbos and putting Tefillin.

I was wondering if this exception also includes the mezouzot. Since one studies the shema in his home everyday. Are there any restrictions on this. I can't seem to find any halachic sources.