--- avrdude-5.5/stk500.c	2007-03-26 07:14:35.000000000 +0200
+++ avrdude-5.5/stk500.c	2007-07-19 01:54:20.000000000 +0200
@@ -1220,6 +1220,48 @@ 
   stk500_print_parms1(pgm, "");
 }
 
+/* Signature byte reads are always 3 bytes. */
+static int stk500_read_sig_bytes(PROGRAMMER * pgm, AVRPART * p, AVRMEM * m)
+{
+  unsigned char buf[32];
+  unsigned char tmp;
+
+  if (m->size < 3) {
+    fprintf(stderr, "%s: memsize too small for sig byte read", progname);
+    return -1;
+  }
+
+  buf[0] = Cmnd_STK_READ_SIGN;
+  buf[1] = Sync_CRC_EOP;
+     
+  stk500_send(pgm, buf, 2);
+  
+  if (stk500_recv(pgm, buf, 5) < 0)
+    return -1;
+  if (buf[0] == Resp_STK_NOSYNC) {
+    fprintf(stderr, "%s: stk500_cmd(): programmer is out of sync\n", progname);
+    return -1;
+  } else if (buf[0] != Resp_STK_INSYNC) {
+    fprintf(stderr,
+            "\n%s: stk500_read_sig_bytes(): (a) protocol error, "
+            "expect=0x%02x, resp=0x%02x\n", 
+            progname, Resp_STK_INSYNC, buf[0]);
+    return -2;
+  }
+  if (buf[4] != Resp_STK_OK) {
+    fprintf(stderr,
+            "\n%s: stk500_read_sig_bytes(): (a) protocol error, "
+            "expect=0x%02x, resp=0x%02x\n", 
+            progname, Resp_STK_OK, buf[4]);
+    return -3;
+  }
+  
+  m->buf[0] = buf[1];
+  m->buf[1] = buf[2];
+  m->buf[2] = buf[3];
+
+  return 3;
+}
 
 void stk500_initpgm(PROGRAMMER * pgm)
 {
@@ -1250,5 +1292,6 @@ 
   pgm->set_varef      = stk500_set_varef;
   pgm->set_fosc       = stk500_set_fosc;
   pgm->set_sck_period = stk500_set_sck_period;
+  pgm->read_sig_bytes = stk500_read_sig_bytes;
   pgm->page_size      = 256;
 }