diff --git a/apps/codeprop/codeprop-tmp.c b/apps/codeprop/codeprop-tmp.c
index 662cf94b2..d766d6bf2 100644
--- a/apps/codeprop/codeprop-tmp.c
+++ b/apps/codeprop/codeprop-tmp.c
@@ -28,7 +28,7 @@
  *
  * This file is part of the Contiki operating system.
  *
- * @(#)$Id: codeprop-tmp.c,v 1.3 2006/12/18 15:17:47 fros4943 Exp $
+ * @(#)$Id: codeprop-tmp.c,v 1.4 2007/03/18 13:15:01 ksb Exp $
  */
 
 /** \addtogroup esb
@@ -115,6 +115,7 @@ struct codeprop_udphdr {
 
 struct codeprop_tcphdr {
   u16_t len;
+  u16_t pad;
 };
 
 static void uipcall(void *state);
diff --git a/apps/codeprop/codeprop.h b/apps/codeprop/codeprop.h
index acec1b436..4b5f967db 100644
--- a/apps/codeprop/codeprop.h
+++ b/apps/codeprop/codeprop.h
@@ -28,7 +28,7 @@
  *
  * This file is part of the Contiki operating system.
  *
- * @(#)$Id: codeprop.h,v 1.1 2006/06/18 07:44:36 adamdunkels Exp $
+ * @(#)$Id: codeprop.h,v 1.2 2007/03/18 13:15:01 ksb Exp $
  */
 #ifndef __CODEPROP_H__
 #define __CODEPROP_H__
@@ -39,6 +39,7 @@
 
 struct codeprop_tcphdr {
   u16_t len;
+  u16_t pad;
 };
 
 PROCESS_NAME(codeprop_process);
diff --git a/cpu/at91sam7s/loader/codeprop-otf.c b/cpu/at91sam7s/loader/codeprop-otf.c
index 38e6b421f..263982487 100644
--- a/cpu/at91sam7s/loader/codeprop-otf.c
+++ b/cpu/at91sam7s/loader/codeprop-otf.c
@@ -28,7 +28,7 @@
  *
  * This file is part of the Contiki operating system.
  *
- * @(#)$Id: codeprop-otf.c,v 1.1 2007/03/07 16:07:26 ksb Exp $
+ * @(#)$Id: codeprop-otf.c,v 1.2 2007/03/18 13:15:02 ksb Exp $
  */
 
 /** \addtogroup esb
@@ -117,6 +117,7 @@ struct codeprop_udphdr {
 
 struct codeprop_tcphdr {
   u16_t len;
+  u16_t pad;
 };
 
 static void uipcall(void *state);
@@ -366,7 +367,7 @@ PT_THREAD(recv_udpthread(struct pt *pt))
 }
 /*---------------------------------------------------------------------*/
 
-#define CODEPROP_TCPHDR_SIZE 2
+#define CODEPROP_TCPHDR_SIZE sizeof(struct codeprop_tcphdr)
 
 static
 PT_THREAD(recv_tcpthread(struct pt *pt))
diff --git a/platform/stepper-robot/Makefile b/platform/stepper-robot/Makefile
index 35ee47aca..09972d548 100644
--- a/platform/stepper-robot/Makefile
+++ b/platform/stepper-robot/Makefile
@@ -33,10 +33,13 @@ CFLAGS+= -I stepper
 
 cfs-ram.o: CFLAGS+= -DCFS_RAM_CONF_SIZE=4096
 
-all: $(KERNELS)
+all: $(KERNELS) codeprop
 
 sys-tst.elf: sys-tst.o $(ARCH) $(SYSTEM)
 
 robot-main-syms.elf:  robot-main.o stepper-process.o $(ARCH) $(SYSTEM) $(SYSLIB) $(UIP) $(UIPDRIVERS) $(STEPPER) $(CODEPROP) $(DEBUG_IO)
 
+codeprop: $(CONTIKI)/tools/codeprop.c
+	cc -g -Wall $< -o $@
+
 include $(CONTIKI)/cpu/at91sam7s/Makefile.at91sam7s
diff --git a/tools/codeprop.c b/tools/codeprop.c
index ff4d8208c..3e66bf080 100644
--- a/tools/codeprop.c
+++ b/tools/codeprop.c
@@ -28,7 +28,7 @@
  *
  * This file is part of the Contiki operating system.
  *
- * @(#)$Id: codeprop.c,v 1.2 2006/08/02 14:33:37 bg- Exp $
+ * @(#)$Id: codeprop.c,v 1.3 2007/03/18 13:15:00 ksb Exp $
  */
 #include <stdlib.h>
 #include <stdio.h>
@@ -48,6 +48,9 @@
 #include <netinet/in.h>
 #include <arpa/inet.h>
 
+/* Should be included from codeprop.h, but the include paths in the makefiles
+   isn't set up for that. */
+#define HDR_SIZE 4
 
 int
 main(int argc, char **argv) {
@@ -96,7 +99,7 @@ main(int argc, char **argv) {
     char buf[64000];
     int len;
     
-    len = read(fd, &buf[2], sizeof(buf) - 2);
+    len = read(fd, &buf[HDR_SIZE], sizeof(buf) - HDR_SIZE);
     if(len == 0) {
       printf("File successfully sent (%d bytes)\n", total);
       len = read(s, buf, sizeof(buf));
@@ -118,7 +121,7 @@ main(int argc, char **argv) {
     total += len;
     buf[0] = len >> 8;
     buf[1] = len & 0xff;
-    if(write(s, buf, len + 2) == -1) {
+    if(write(s, buf, len + HDR_SIZE) == -1) {
       perror("network send failed");
       exit(1);
     }