diff --git a/ChangeLog b/ChangeLog
index c310e7818..d9b36dbc4 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -4,6 +4,8 @@
 	When calculating info about a structure, make sure its alignment is
 	that of its most strictly aligned field and make sure its size is a
 	multiple of its alignment.
+	* Source/NSData.m: ([initWithCoder:]) Fix bug decoding unsigned long
+	into unsigned int variable ... breaks on amd64
 
 2006-01-10  Richard Frith-Macdonald <rfm@gnu.org>
 
diff --git a/Source/NSData.m b/Source/NSData.m
index b54b972c1..0ee5b437c 100644
--- a/Source/NSData.m
+++ b/Source/NSData.m
@@ -1770,7 +1770,7 @@ failure:
   unsigned	length = [self length];
   void		*bytes = [self mutableBytes];
 
-  [aCoder encodeValueOfObjCType: @encode(unsigned long)
+  [aCoder encodeValueOfObjCType: @encode(unsigned int)
 			     at: &length];
   if (length)
     {
@@ -1802,7 +1802,7 @@ failure:
   zone = [self zone];
 #endif
 
-  [aCoder decodeValueOfObjCType: @encode(unsigned long) at: &l];
+  [aCoder decodeValueOfObjCType: @encode(unsigned int) at: &l];
   if (l)
     {
       void	*b = NSZoneMalloc(zone, l);