lib/PublicInbox/HTTP.pm | 2 +-

diff --git a/lib/PublicInbox/HTTP.pm b/lib/PublicInbox/HTTP.pm
index 669211e38099fbacf3e4b4309deeced1568c5d00..3d4e34995dfbd9f11749c052ec7f6766331177f5 100644
--- a/lib/PublicInbox/HTTP.pm
+++ b/lib/PublicInbox/HTTP.pm
@@ -135,7 +135,7 @@ 	$self->{env} = undef; # for exists() check in ->busy
 	$env->{REMOTE_ADDR} = $self->{remote_addr};
 	$env->{REMOTE_PORT} = $self->{remote_port};
 	if (defined(my $host = $env->{HTTP_HOST})) {
-		$host =~ s/:([0-9]+)\z// and $env->{SERVER_PORT} = $1;
+		$host =~ s/:([0-9]+)\z// and $env->{SERVER_PORT} = $1 + 0;
 		$env->{SERVER_NAME} = $host;
 	}
 	if (defined $input) {