diff --git a/lib/net/imap.rb b/lib/net/imap.rb
index 61ce520177..4debec8d54 100644
--- a/lib/net/imap.rb
+++ b/lib/net/imap.rb
@@ -999,7 +999,7 @@ module Net
     def self.decode_utf7(s)
       return s.gsub(/&([^-]+)?-/n) {
         if $1
-          ($1.tr(",", "/") + "===").unpack("m")[0].encode(Encoding::UTF_8, Encoding::UTF_16BE)
+          ($1.tr(",", "/") + "===").unpack1("m").encode(Encoding::UTF_8, Encoding::UTF_16BE)
         else
           "&"
         end