[CR]brush on rimstrip?

(Example: Events:Cirque du Cyclisme:2004)

Date: Sat, 09 Sep 2006 17:28:37 -0700
From: "Bob Freitas" <freitas1@pacbell.net>
To: CLASSIC RENDEZVOUS <classicrendezvous@bikelist.org>
Subject: [CR]brush on rimstrip?

I just came across a wheel that seemed to be treated with a brush in material that covered the well of the rim and also partially filled the spoke holes. anyone know of this? It has to be post 1980 as I have never seen it before.
     Just spent quite a bit of time digging it out as I think it is the reason for a very tight fitting tire
                                              BOB FREITAS
                                         MILL VALLEY,CA