A trademark add-on to the AGPL license

[Thomas Goirand <thomas@goirand.fr>]

Hi,

I would like to package z-push in Debian. It seems to me that it's ok to
ship it in Debian, but I'm not sure if it's ok to keep the upstream name
z-push, due to some addition to the AGPL license.

Here's home pages for z-push:
http://z-push.sourceforge.net/soswp/index.php?pages_id=39&t=Download
https://community.zarafa.com/pg/plugins/project/5/developer/sebastian/zpush

Here's how it reads:

However, if you propagate an unmodified version of the Program you are
allowed to use the term "Z-Push" to indicate that you distribute the
Program.

Furthermore you may use our trademarks where it is necessary to indicate
the intended purpose of a product or service provided you use it in
accordance with honest practices in industrial or commercial matters.

If you want to propagate modified versions of the Program under the name
"Z-Push", you may only do so if you have a written permission by Zarafa
Deutschland GmbH (to acquire a permission please contact Zarafa at
trademark@zarafa.com).

Any legal advice would be welcome.

I have Cc: the upstream author called Sebastian. Sebastian, your
addition to the AGPL license may be in direct conflict with a major rule
in debian. Namely, point 1 of the DFSG, as seen here:
http://www.debian.org/social_contract

Your addition may well render your package not redistributable in Debian
under the name z-push. I'm not 100% sure yet, it might be ok to
redistribute it as long as your original source code stays unmodified in
the source package. Anyway, what is for sure, is that it makes it more
difficult than a normal, unmodified, AGPL license. Would you consider
removing such AGPL "add-on"? I don't think it's needed to protect your
trademark. Look at the BSD-3-clause license, for a good example of
clauses doing so.

Cheers,

Thomas Goirand (zigo)