OpenID URLs aren't clickable in the ViewVC logs because they're directly followed by a colon. At the expense of, um, proper grammar, here's a patch for SVN. If this is OK, I'll patch the other RCS modules, too.
--- IkiWiki/Rcs/svn.pm  (revision 2650)
+++ IkiWiki/Rcs/svn.pm  (working copy)
@@ -71,7 +71,7 @@
        my $ipaddr=shift;
 
        if (defined $user) {
-               $message="web commit by $user".(length $message ? ": $message" : "");
+               $message="web commit by $user ".(length $message ? ": $message" : "");
        }
        elsif (defined $ipaddr) {
                $message="web commit from $ipaddr".(length $message ? ": $message" : "");