lib/PublicInbox/GitCatFile.pm | 3 ++-
 lib/PublicInbox/NNTP.pm       | 5 +++--

diff --git a/lib/PublicInbox/GitCatFile.pm b/lib/PublicInbox/GitCatFile.pm
index 4f16762e56c8959eaaed4c7d91d3a7e647f7e729..dd3f2912cc2715d6a9ffd8449b2adce883db48a6 100644
--- a/lib/PublicInbox/GitCatFile.pm
+++ b/lib/PublicInbox/GitCatFile.pm
@@ -38,7 +38,7 @@ 	$self->{pid} = $pid;
 }
 
 sub cat_file {
-	my ($self, $object) = @_;
+	my ($self, $object, $sizeref) = @_;
 
 	$object .= "\n";
 	my $len = bytes::length($object);
@@ -58,6 +58,7 @@ 	$head =~ /^[0-9a-f]{40} \S+ (\d+)$/ or
 		die "Unexpected result from git cat-file: $head\n";
 
 	my $size = $1;
+	$$sizeref = $size if $sizeref;
 	my $bytes_left = $size;
 	my $offset = 0;
 	my $rv = '';
diff --git a/lib/PublicInbox/NNTP.pm b/lib/PublicInbox/NNTP.pm
index d5eb4971b845568fa8fbbe8482eff2201889f202..fb93330b43aaffa18374def94d77935acf2f9ccc 100644
--- a/lib/PublicInbox/NNTP.pm
+++ b/lib/PublicInbox/NNTP.pm
@@ -366,7 +366,8 @@ 		defined $mid or return $err;
 	}
 found:
 	my $o = 'HEAD:' . mid2path($mid);
-	my $s = eval { Email::Simple->new($ng->gcf->cat_file($o)) };
+	my $bytes;
+	my $s = eval { Email::Simple->new($ng->gcf->cat_file($o, \$bytes)) };
 	return $err unless $s;
 	if ($set_headers) {
 		$s->header_set('Newsgroups', $ng->{name});
@@ -375,7 +376,7 @@ 		$s->header_set('Xref', xref($ng, $n));
 
 		# must be last
 		if ($set_headers == 2) {
-			$s->header_set('Bytes', bytes::length($s->as_string));
+			$s->header_set('Bytes', $bytes);
 			$s->body_set('');
 		}
 	}