diff --git a/ChangeLog b/ChangeLog
index 27c621a8b3..08caae730a 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Fri Mar 14 10:03:59 2008  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* string.c (UNALIGNED_WORD_ACCESS): IA64 cannot access unaligned word.
+
 Thu Mar 13 21:00:50 2008  Yukihiro Matsumoto  <matz@ruby-lang.org>
 
 	* array.c (rb_ary_slice_bang): should not use rb_ary_subseq()
diff --git a/string.c b/string.c
index 39a96ee848..fc7ed7c641 100644
--- a/string.c
+++ b/string.c
@@ -1689,7 +1689,7 @@ rb_str_concat(VALUE str1, VALUE str2)
     return rb_str_append(str1, str2);
 }
 
-#if defined __i386__ || defined _M_IX86 || defined __ia64
+#if defined __i386__ || defined _M_IX86
 #define UNALIGNED_WORD_ACCESS 1
 #endif
 #ifndef UNALIGNED_WORD_ACCESS