diff --git a/avrdude/ChangeLog b/avrdude/ChangeLog
index 7e3b175c..d2a65525 100644
--- a/avrdude/ChangeLog
+++ b/avrdude/ChangeLog
@@ -1,3 +1,7 @@
+2005-10-20  Joerg Wunsch <j@uriah.heep.sax.de>
+
+	* butterfly.c: fix yet another sign extension bug.
+
 2005-10-14  Joerg Wunsch <j@uriah.heep.sax.de>
 
 	* avrdude.conf.in (ATmega8515): fix size of calibration
diff --git a/avrdude/butterfly.c b/avrdude/butterfly.c
index b64a3aca..ce3aad73 100644
--- a/avrdude/butterfly.c
+++ b/avrdude/butterfly.c
@@ -297,9 +297,9 @@ static int butterfly_initialize(PROGRAMMER * pgm, AVRPART * p)
     exit(1);
   };
   butterfly_recv(pgm, &c, 1);
-  buffersize = c<<8;
+  buffersize = (unsigned int)(unsigned char)c<<8;
   butterfly_recv(pgm, &c, 1);
-  buffersize += c;
+  buffersize += (unsigned int)(unsigned char)c;
   fprintf(stderr,
     "Programmer supports buffered memory access with buffersize=%i bytes.\n",
      buffersize);