diff --git a/Makefile b/Makefile
index 7e0a1c6e..7835a2a8 100644
--- a/Makefile
+++ b/Makefile
@@ -2,7 +2,7 @@ RELEASE=2.2
 
 VERSION=2.0
 PACKAGE=qemu-server
-PKGREL=62
+PKGREL=63
 
 DESTDIR=
 PREFIX=/usr
@@ -35,10 +35,10 @@ vzsyscalls.ph: vzsyscalls.h
 	 h2ph -d . vzsyscalls.h
 
 vmtar: vmtar.c utils.c
-	gcc -O2 -Wall -o vmtar vmtar.c
+	gcc -O2 -Werror -Wall -Wtype-limits -o vmtar vmtar.c
 
 sparsecp: sparsecp.c utils.c
-	gcc -O2 -Wall -o sparsecp sparsecp.c
+	gcc -O2 -Werror -Wall -Wtype-limits -o sparsecp sparsecp.c
 
 %.1.gz: %.1.pod
 	rm -f $@
diff --git a/changelog.Debian b/changelog.Debian
index 285ba63f..ef17485a 100644
--- a/changelog.Debian
+++ b/changelog.Debian
@@ -1,3 +1,9 @@
+qemu-server (2.0-63) unstable; urgency=low
+
+  * fix bug in vmtar 
+
+ -- Proxmox Support Team <support@proxmox.com>  Thu, 25 Oct 2012 10:00:50 +0200
+
 qemu-server (2.0-62) unstable; urgency=low
 
   * vncproxy: wait until vnc port is ready
diff --git a/utils.c b/utils.c
index 5187940e..c69e0ef5 100644
--- a/utils.c
+++ b/utils.c
@@ -68,7 +68,7 @@ safe_read(int fd, char *buf, size_t count)
 int 
 full_read(int fd, char *buf, size_t len)
 {
-  size_t n;
+  ssize_t n;
   size_t total;
 
   total = 0;
@@ -110,7 +110,7 @@ safe_write(int fd, char *buf, size_t count)
 int 
 full_write(int fd, char *buf, size_t len)
 {
-  size_t n;
+  ssize_t n;
   size_t total;
 
   total = 0;
diff --git a/vmtar.c b/vmtar.c
index 6b34a88b..29160b82 100644
--- a/vmtar.c
+++ b/vmtar.c
@@ -402,7 +402,7 @@ dump_sparse_file (int fd, struct writebuffer *wbuf, struct sp_array *ma)
 
     while (bytes_left > 0) {
       size_t bufsize = (bytes_left > BLOCKSIZE) ? BLOCKSIZE : bytes_left;
-      size_t bytes_read;
+      ssize_t bytes_read;
 
       char *blkbuf = buffer_block (wbuf);
       if ((bytes_read = full_read (fd, blkbuf, bufsize)) < 0) {