thread: fix comment describing its existence

Mail::Thread is UNavailable on many distros, meaning ordinary
users will have to rely on CPAN, a Perl-specific packaging tool.

diff --git a/lib/PublicInbox/SearchThread.pm b/lib/PublicInbox/SearchThread.pm
index fe70406b0cbad163f2b52f23d9bda019367e55d4..5774a9562b55f27956fd8e8e1baad11389e95e08 100644 (file)
--- a/lib/PublicInbox/SearchThread.pm
+++ b/lib/PublicInbox/SearchThread.pm
@@ -4,7 +4,7 @@
 # This license differs from the rest of public-inbox
 #
 # Our own jwz-style threading class based on Mail::Thread from CPAN.
-# Mail::Thread is unmaintained and available on some distros.
+# Mail::Thread is unmaintained and unavailable on some distros.
 # We also do not want pruning or subject grouping, since we want
 # to encourage strict threading and hopefully encourage people
 # to use proper In-Reply-To.