diff -uNr tar-1.23.ORIG//src/create.c tar-1.23/src/create.c
--- tar-1.23.ORIG//src/create.c	2010-04-25 17:36:03.553606076 +0100
+++ tar-1.23/src/create.c	2010-04-25 17:36:16.294605862 +0100
@@ -575,7 +575,10 @@
   GNAME_TO_CHARS (tmpname, header->header.gname);
   free (tmpname);
 
-  strcpy (header->header.magic, OLDGNU_MAGIC);
+  /* OLDGNU_MAGIC is string with 7 chars + NULL */
+  strncpy (header->header.magic, OLDGNU_MAGIC, sizeof(header->header.magic));
+  strncpy (header->header.version, OLDGNU_MAGIC+sizeof(header->header.magic),
+           sizeof(header->header.version));
   header->header.typeflag = type;
   finish_header (st, header, -1);
 
@@ -910,9 +913,13 @@
       break;
 
     case OLDGNU_FORMAT:
-    case GNU_FORMAT:   /*FIXME?*/
-      /* Overwrite header->header.magic and header.version in one blow.  */
-      strcpy (header->header.magic, OLDGNU_MAGIC);
+    case GNU_FORMAT:
+      /* OLDGNU_MAGIC is string with 7 chars + NULL */
+      strncpy (header->header.magic, OLDGNU_MAGIC,
+               sizeof(header->header.magic));
+      strncpy (header->header.version,
+               OLDGNU_MAGIC+sizeof(header->header.magic),
+               sizeof(header->header.version));
       break;
 
     case POSIX_FORMAT: