Unable to modify include directory in BCB 4

I am unable to get the include field in the Directories tab of the
Project
Options to contain the project directory I have my project include
files in.
Why won't this field allow my project directory to be included?  I am
operating in Win 98.
I got around it by using the file search for my headers with the ""
around
the file spec instead of the <>.  I would like to eliminate this and
use
only the <>.
Thanks,
Czara