diff --git a/ChangeLog b/ChangeLog
index 6eab773132..45c755de17 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Thu Dec  4 09:12:43 2003  GOTOU Yuuzou  <gotoyuzo@notwork.org>
+
+	* ext/openssl/ossl_asn1.c (asn1time_to_time): should check that
+	  the underlying value of ASN1_TIME isn't NULL.
+
 Thu Dec  4 08:29:43 2003  GOTOU Yuuzou  <gotoyuzo@notwork.org>
 
 	* lib/webrick/server.rb (GenericServer#start): should rescue
diff --git a/ext/openssl/ossl_asn1.c b/ext/openssl/ossl_asn1.c
index 02d2f2cafb..f0d8dda9b8 100644
--- a/ext/openssl/ossl_asn1.c
+++ b/ext/openssl/ossl_asn1.c
@@ -28,9 +28,7 @@ asn1time_to_time(ASN1_TIME *time)
     struct tm tm;
     VALUE argv[6];
     
-    if (!time) {
-	ossl_raise(rb_eTypeError, "ASN1_TIME is NULL!");
-    }
+    if (!time || !time->data) return Qnil;
     memset(&tm, 0, sizeof(struct tm));
 	
     switch (time->type) {