diff --git a/lib/dns/masterdump.c b/lib/dns/masterdump.c
index 9a31c0000e..b069e40123 100644
--- a/lib/dns/masterdump.c
+++ b/lib/dns/masterdump.c
@@ -15,7 +15,7 @@
  * PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: masterdump.c,v 1.104 2011/03/11 06:11:23 marka Exp $ */
+/* $Id: masterdump.c,v 1.105 2011/03/18 09:00:44 fdupont Exp $ */
 
 /*! \file */
 
@@ -1387,23 +1387,24 @@ dumptostreaminc(dns_dumpctx_t *dctx) {
 			isc_buffer_region(&buffer, &r);
 			isc_buffer_putuint32(&buffer, dns_masterformat_raw);
 			isc_buffer_putuint32(&buffer, DNS_RAWFORMAT_VERSION);
-			if (sizeof(now32) != sizeof(dctx->now)) {
-				/*
-				 * We assume isc_stdtime_t is a 32-bit integer,
-				 * which should be the case on most cases.
-				 * If it turns out to be uncommon, we'll need
-				 * to bump the version number and revise the
-				 * header format.
-				 */
-				isc_log_write(dns_lctx,
-					      ISC_LOGCATEGORY_GENERAL,
-					      DNS_LOGMODULE_MASTERDUMP,
-					      ISC_LOG_INFO,
-					      "dumping master file in raw "
-					      "format: stdtime is not 32bits");
-				now32 = 0;
-			} else
-				now32 = dctx->now;
+#if !defined(STDTIME_ON_32BITS) || (STDTIME_ON_32BITS + 0) != 1
+			/*
+			 * We assume isc_stdtime_t is a 32-bit integer,
+			 * which should be the case on most cases.
+			 * If it turns out to be uncommon, we'll need
+			 * to bump the version number and revise the
+			 * header format.
+			 */
+			isc_log_write(dns_lctx,
+				      ISC_LOGCATEGORY_GENERAL,
+				      DNS_LOGMODULE_MASTERDUMP,
+				      ISC_LOG_INFO,
+				      "dumping master file in raw "
+				      "format: stdtime is not 32bits");
+			now32 = 0;
+#else
+			now32 = dctx->now;
+#endif
 			isc_buffer_putuint32(&buffer, now32);
 			INSIST(isc_buffer_usedlength(&buffer) <=
 			       sizeof(rawheader));
diff --git a/lib/isc/unix/include/isc/stdtime.h b/lib/isc/unix/include/isc/stdtime.h
index 4cb9e81fa6..6c31c0d219 100644
--- a/lib/isc/unix/include/isc/stdtime.h
+++ b/lib/isc/unix/include/isc/stdtime.h
@@ -15,7 +15,7 @@
  * PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: stdtime.h,v 1.14 2007/06/19 23:47:19 tbox Exp $ */
+/* $Id: stdtime.h,v 1.15 2011/03/18 09:00:44 fdupont Exp $ */
 
 #ifndef ISC_STDTIME_H
 #define ISC_STDTIME_H 1
@@ -31,6 +31,10 @@
  * about its size.
  */
 typedef isc_uint32_t isc_stdtime_t;
+
+/* but this flag helps... */
+#define STDTIME_ON_32BITS	1
+
 /*
  * isc_stdtime32_t is a 32-bit version of isc_stdtime_t.  A variable of this
  * type should only be used as an opaque integer (e.g.,) to compare two
diff --git a/lib/isc/win32/include/isc/stdtime.h b/lib/isc/win32/include/isc/stdtime.h
index 4f9eb74c54..b5e89cf74d 100644
--- a/lib/isc/win32/include/isc/stdtime.h
+++ b/lib/isc/win32/include/isc/stdtime.h
@@ -15,7 +15,7 @@
  * PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: stdtime.h,v 1.12 2007/06/19 23:47:20 tbox Exp $ */
+/* $Id: stdtime.h,v 1.13 2011/03/18 09:00:45 fdupont Exp $ */
 
 #ifndef ISC_STDTIME_H
 #define ISC_STDTIME_H 1
@@ -29,6 +29,10 @@
  * about its size.
  */
 typedef isc_uint32_t isc_stdtime_t;
+
+/* but this flag helps... */
+#define STDTIME_ON_32BITS	1
+
 /*
  * isc_stdtime32_t is a 32-bit version of isc_stdtime_t.  A variable of this
  * type should only be used as an opaque integer (e.g.,) to compare two