retrieving log messages by revision

[Harry Putnam]

I'm sure its a basic operation, to retrieve log messages for a
specific revision of something, but I'm not catching on after banging
around in the manual a bit it appears that this should do what I'm
after.

cvs log -r7 some/file

But when I run that command the output does not contain the log
message.

,----
| cvs log -r7 reader/home/reader/lisp/site-start.el
|
| RCS file: /usr/local/cvsroot/base/reader/home/reader/lisp/site-start.el,v
| Working file: reader/home/reader/lisp/site-start.el
| head: 1.7
| branch:
| locks: strict
| access list:
| symbolic names:
|         start-100227_222841: 1.1.1.1
|         hp-100227_222841: 1.1.1
| keyword substitution: kv
| total revisions: 8;     selected revisions: 0
| description:
`----

So I must be missing something basic.

A similar command but much more inclusive:
   cvs log reader/home/reader/lisp/site-start.el

Does show the log message for that revision.

,----
| cvs log reader/home/reader/lisp/site-start.el |
|         grep -B1 -A4 'revision 1.7'
| (Just showing the desired output)
|  ----------------------------
| revision 1.7
| date: 2011-10-17 08:23:02 -0500;  author: root;  state: Exp;  lines: +43 -37; 
 commitid: 6AUYI0mEJAtRNHDv;
| Changed all skeletons and etc, that ouput
| formatted dates to the format yymmdd_HH:MM:SS
| ----------------------------
`----

How can I use `cvs log' to retrieve a specific revisions commit
message if any?