diff --git a/lib/Plack/Request.pm b/lib/Plack/Request.pm
index 2b094545..437d322b 100644
--- a/lib/Plack/Request.pm
+++ b/lib/Plack/Request.pm
@@ -95,7 +95,7 @@ sub headers {
                 (my $field = $_) =~ s/^HTTPS?_//;
                 ( lc($field) => $env->{$_} );
             }
-                grep { /^(?:HTTP|CONTENT)/i } keys %$env
+                grep { /^(?:HTTP|CONTENT)_/ } keys %$env
             );
     }
     $self->{headers};
diff --git a/t/Plack-Request/upload.t b/t/Plack-Request/upload.t
index cf888a45..e78fc38b 100644
--- a/t/Plack-Request/upload.t
+++ b/t/Plack-Request/upload.t
@@ -20,6 +20,8 @@ my $app = sub {
     is $files[1]->filename, 'foo2.txt';
     ok -e $files[0]->tempname;
 
+    unlike $req->headers->as_string, qr/Multipart\.Tempdir/;
+
     is join(', ', sort { $a cmp $b } $req->upload()), 'bar, foo';
 
     for (qw(foo bar)) {