lib/PublicInbox/NewsWWW.pm | 2 +-

diff --git a/lib/PublicInbox/NewsWWW.pm b/lib/PublicInbox/NewsWWW.pm
index 8626cf96eaba44acee92a10a2aa3d84fcb7ab788..80bb488622f41095fc619bdcc5ee0b5682513ffe 100644
--- a/lib/PublicInbox/NewsWWW.pm
+++ b/lib/PublicInbox/NewsWWW.pm
@@ -47,7 +47,7 @@ 	my $pi_config = $self->{pi_config};
 	if (my $ibx = $pi_config->lookup_newsgroup($ng)) {
 		my $url = PublicInbox::Hval::prurl($env, $ibx->{url});
 		my $code = 301;
-		if (defined $article && $article =~ /\A\d+\z/) {
+		if (defined $article && $article =~ /\A[0-9]+\z/) {
 			my $mid = eval { $ibx->mm->mid_for($article) };
 			if (defined $mid) {
 				# article IDs are not stable across clones,