BUG #6652: Installer grants postgres user rights for the whole disk, not specified subfolder

The following bug has been logged on the website:

Bug reference:      6652
Logged by:          Basil Peace
Email address:      grv87@yandex.ru
PostgreSQL version: 9.1.3
Operating system:   Windows 7 x64
Description:=20=20=20=20=20=20=20=20

I have been installing PostgreSQL 9.1.3.2, and I've noted that 'creating
database cluster' is too long. I have been waiting for a half of hour, and
it hasn't finished.
I've noted that installer calls icacls.exe with arguments:
D:\ /grant "postgres":RX=20

My database is wanted to be in D:\Sys\pgsql-data
There is no reason for granting rights for the whole disk. I have more than
3 mln files there, and of course it could be a big waste of time.