diff --git a/lib/net/pop.rb b/lib/net/pop.rb
index 046763e0a8..a6c002ce0c 100644
--- a/lib/net/pop.rb
+++ b/lib/net/pop.rb
@@ -337,20 +337,14 @@ Net::POP3
     end
 
 
-    def auth( acnt, pass )
+    def auth( account, pass )
       critical {
-        @socket.writeline( "APOP #{acnt} #{digest(@stamp + pass)}" )
+        @socket.writeline sprintf( 'APOP %s %s',
+                            account, MD5.new(@stamp + pass).hexdigest )
         check_reply_auth
       }
     end
 
-
-    def digest( str )
-      ret = ''
-      MD5.new( str ).digest.each_byte {|i| ret << sprintf('%02x', i) }
-      ret
-    end
-      
   end
 
 end
diff --git a/lib/net/protocol.rb b/lib/net/protocol.rb
index 1d909bbb4b..399b2bbdd4 100644
--- a/lib/net/protocol.rb
+++ b/lib/net/protocol.rb
@@ -15,8 +15,6 @@ require 'socket'
 
 module Net
 
-  Version = '1.1.17'
-
 =begin
 
 == Net::Protocol
@@ -68,7 +66,7 @@ Object
 
   class Protocol
 
-    Version = ::Net::Version
+    Version = '1.1.18'
 
     class << self
 
@@ -165,7 +163,7 @@ Object
         connect
         do_start *args
         @active = true
-        yield if iterator?
+        yield self if iterator?
       ensure
         finish if iterator?
       end
@@ -591,7 +589,7 @@ Object
       do_write_do D_CRLF
       wsize = do_write_fin
 
-      @pipe << "wrote #{wsize} bytes text" if pipeon
+      @pipe << "wrote #{wsize} bytes text\n" if pipeon
       wsize
     end
 
diff --git a/lib/net/smtp.rb b/lib/net/smtp.rb
index fe3dd9e1b2..35e9118df8 100644
--- a/lib/net/smtp.rb
+++ b/lib/net/smtp.rb
@@ -109,9 +109,10 @@ Net::Protocol
     def do_start( helodom = nil,
                   user = nil, secret = nil, authtype = nil )
       unless helodom then
-        helodom = ENV['HOSTNAME'] || ENV['HOST']
+        helodom = ::Socket.gethostname
         unless helodom then
-          raise ArgumentError, "cannot get hostname"
+          raise ArgumentError,
+            "cannot get localhost name; try 'smtp.start(local_host_name)'"
         end
       end