Individual repository permission management in SVN?

[cube 316 <cu...@gmail.com>]

Hi, guys:

I've been using SVN for a couple of days with the "SVNParentPath"
configuration, and all the repositories share the same password file and
access file.

here's the question:

in order to reduce the workload for the sysop, we'd like to setup individual
permissions for each repository.
which means, let the owner of each repository do the user and access policy
maintenance instead of the system administrator.

as long as I know, CVS has such feature, that's to say:

1.setup two repositories, called RA and RB, assign all the privileges of RA
to AdminRA, and RB's to AdminRB.
2.create a password file in RA / CVSRoot, whose format is like this:

     # suppose file name is: passwdRA
     userA1:[encrypted_password]:AdminA
     userA2:[encrypted_password]:AdminA

3.meanwhile, RA has an access file.
4.so when RA need to add a new user, AdminRA have to login using SSH or so,
edit file "passwdRA", and the access file as well.
   there's no necessity to inform the sysop to do this.
5.AdminRB can do similar operations to RB
6.all the changed are affected in side their own repository(RA or RB here)
and is much safer.

so any solutions to achieve this goal in SVN ? ( I do NOT expect to use
mysql authorization )

thanks in advance!

Regards.
cube316