[Exim] Request fix for users to be able to use accounts named like "system reserved filenames"

Gents,

I have users on my systems which use mail addresses like:

shadow@domain.tld

Unfortunately cPanel uses a file system based system for mail users thus

the username collides with the cPanel default directory for

"virtual_user_filters". (I had no problems with the same users on the

old server (Plesk 10) as it used a database based user management for

mail users)

So when a user is receiving mail in any direction (even if it's just a

simple forwarding domain) it results in the following error

"--> 2013-01-21 18:34:30 1TxLGQ-0002EA-2M == shadow@domain.tld

R=virtual_user_filter defer (-1): require_files: error for

/home/<account>/etc/<domain.tld>/shadow/filter: Not a

directory"

that is caused by the fact that "

/home/<account>/etc/<domain.tld>/shadow" is the standard

unix shadow - file for the corresponding user. A possible fix is to

relocate the vfilter search path to e.g.

"/home/<account>/etc/<domain.tld>/vfilter/"

Sadly it's easier said than done. One need to modify the /etc/exim.conf

manually, but given the base expectation of automated updates these

changes are overwritten by the time an update takes place.

Therefore the idea was to edit the template file (

/usr/local/cpanel/etc/exim/distconfig/exim.conf.dist ) directly, but the

update even replaces this whole file!

And finally there is no possibility to change the necessary lines via WHM (yes I searched the documentation).

Please see this forum post I've made for a more detailed description (incl. screenshots)

http://forums.cpanel.net/f43/want-file-bug-fix-system-reserved-filenames-email-accounts-318792.html

To make long things short: cPanel needs a way to make these changes permanent. I.e. at least providing a way to change the virtual user filter manually via official configuration channels OR changing this permanently in the cPanel system by moving the default search path like suggested.

Steps to reproduce:

1. Create a mail user with the name "shadow" (forwarding or "real"

mailbox shouldn't matter, but try both variants please since I don't

know to which kind this virtual_user_filter actually applies)

2. Send this user mails.

3. Look at /var/log/exim_mainlog