}
        if ($author =~ /^\s*(.+?)\s*<(.*)>\s*$/) {
                my ($name, $email) = ($1, $2);
-               $email = undef if length $2 == 0;
                return [$name, $email];
        } else {
                die "Author: $orig_author: $::_authors_prog returned "
                remove_username($full_url);
                $log_entry{metadata} = "$full_url\@$r $uuid";
                $log_entry{svm_revision} = $r;
-               $email ||= "$author\@$uuid";
-               $commit_email ||= "$author\@$uuid";
+               $email = "$author\@$uuid" unless defined $email;
+               $commit_email = "$author\@$uuid" unless defined $commit_email;
        } elsif ($self->use_svnsync_props) {
                my $full_url = canonicalize_url(
                        add_path_to_url( $self->svnsync->{url}, $self->path )
                remove_username($full_url);
                my $uuid = $self->svnsync->{uuid};
                $log_entry{metadata} = "$full_url\@$rev $uuid";
-               $email ||= "$author\@$uuid";
-               $commit_email ||= "$author\@$uuid";
+               $email = "$author\@$uuid" unless defined $email;
+               $commit_email = "$author\@$uuid" unless defined $commit_email;
        } else {
                my $url = $self->metadata_url;
                remove_username($url);
                my $uuid = $self->rewrite_uuid || $self->ra->get_uuid;
                $log_entry{metadata} = "$url\@$rev " . $uuid;
-               $email ||= "$author\@" . $uuid;
-               $commit_email ||= "$author\@" . $uuid;
+               $email = "$author\@$uuid" unless defined $email;
+               $commit_email = "$author\@$uuid" unless defined $commit_email;
        }
        $log_entry{name} = $name;
        $log_entry{email} = $email;