return an erro if the servers goes away suddenly.

@@ -1562,6 +1562,11 @@ imap_readline (f_imap_t f_imap)
       if (status != 0)
         return status;
 
+      /* The server went away:  It maybe a timeout and some imap server
+	 does not send the BYE.  Consider like an error.  */
+      if (n == 0)
+	return EIO;
+
       total += n;
       f_imap->offset += n;
       f_imap->nl = memchr (f_imap->buffer, '\n', total);

@@ -538,7 +538,12 @@ pop_open (mailbox_t mbox, int flags)
 	    url_get_auth (mbox->url, auth, sizeof (auth), &n);
 	    if (n == 0 || strcasecmp (auth, "*") == 0)
 	      {
-		authority_create (&(mbox->authority), mbox->ticket, mbox);
+		ticket_t ticket = NULL;
+		if (mbox->folder)
+		  folder_get_ticket (mbox->folder, &ticket);
+		if (ticket == NULL)
+		  ticket = mbox->ticket;
+		authority_create (&(mbox->authority), ticket, mbox);
 		authority_set_authenticate (mbox->authority, pop_user, mbox);
 	      }
 	    else if (strcasecmp (auth, "+apop") == 0)
@@ -1815,6 +1820,11 @@ pop_readline (pop_data_t mpd)
       if (status != 0)
 	return status;
 
+      /* The server went away:  It maybe a timeout and some pop server
+	 does not send the -ERR.  Consider this like an error.  */
+      if (n == 0)
+	return EIO;
+
       total += n;
       mpd->offset += n;
       mpd->nl = memchr (mpd->buffer, '\n', total);

@@ -822,6 +822,10 @@ smtp_readline (smtp_t smtp)
       if (status != 0)
         return status;
 
+      /* Server went away, consider this like an error.  */
+      if (n == 0)
+	return EIO;
+
       total += n;
       smtp->nl = memchr (smtp->buffer, '\n', total);
       if (smtp->nl == NULL)  /* Do we have a full line.  */