<p>Is there a way to edit the log message of a certain revision in Subversion? I accidentally wrote the wrong filename in my commit message which could be confusing later.</p>

<p>I've seen <em><a href="https://stackoverflow.com/questions/179123/how-do-i-edit-an-incorrect-commit-message-in-git">How do I edit an incorrect commit message in Git?</a></em>, but the solution to that question doesn't seem to be similar for Subversion (according to <code>svn help commit</code>).</p>

Essentially you have to have admin rights (directly or indirectly) to the repository to do this.  You can either configure the repository to allow all users to do this, or you can modify the log message directly on the server.
See
this part
of the
Subversion FAQ
(emphasis mine):
Log messages are kept in the
  repository as properties attached to
  each revision.
By default, the log
  message property (svn:log) cannot be
  edited once it is committed
. That is
  because changes to revision properties
  (of which svn:log is one) cause the
  property's previous value to be
  permanently discarded, and Subversion
  tries to prevent you from doing this
  accidentally. However, there are a
  couple of ways to get Subversion to
  change a revision property.
The first way is for the repository
  administrator to enable revision
  property modifications. This is done
  by creating a hook called
  "pre-revprop-change" (see this section
  in the Subversion book for more
  details about how to do this). The
  "pre-revprop-change" hook has access
  to the old log message before it is
  changed, so it can preserve it in some
  way (for example, by sending an
  email). Once revision property
  modifications are enabled, you can
  change a revision's log message by
  passing the --revprop switch to svn
  propedit or svn propset, like either
  one of these:
```
```
$svn propedit -r N --revprop svn:log URL 
$svn propset -r N --revprop svn:log "new log message" URL
```
```
where N
  is the revision number whose log
  message you wish to change, and URL is
  the location of the repository. If you
  run this command from within a working
  copy, you can leave off the URL.
The second way of changing a log
  message is to use svnadmin setlog.
This must be done by referring to the
  repository's location on the
  filesystem. You cannot modify a remote
  repository using this command.
```
```
$ svnadmin setlog REPOS_PATH -r N FILE
```
```
where REPOS_PATH is the repository
  location, N is the revision number
  whose log message you wish to change,
  and FILE is a file containing the new
  log message. If the
  "pre-revprop-change" hook is not in
  place (or you want to bypass the hook
  script for some reason), you can also
  use the --bypass-hooks option.
  However, if you decide to use this
  option, be very careful. You may be
  bypassing such things as email
  notifications of the change, or backup
  systems that keep track of revision
  properties.