This plugin not only locks pages but ensures too a user is logged in. This seems to me redundant with signedit. I propose :

    sub canedit ($$) {
    	my $page=shift;
    	my $cgi=shift;
    	my $session=shift;
    
    	my $user=$session->param("name");
    	return undef if defined $user && IkiWiki::is_admin($user);
    
    	if (defined $config{locked_pages} && length $config{locked_pages} &&
    	    pagespec_match($page, $config{locked_pages},
    		    user => $session->param("name"),
    		    ip => $ENV{REMOTE_ADDR},
    	    )) {
    		return sprintf(gettext("%s is locked and cannot be edited"),
    			htmllink("", "", $page, noimageinline => 1));
    	}
    
    	return undef;
    }