diff --git a/src/jrd/jrd.cpp b/src/jrd/jrd.cpp
index d657a3b4c8..2ba1414abf 100644
--- a/src/jrd/jrd.cpp
+++ b/src/jrd/jrd.cpp
@@ -2405,12 +2405,9 @@ JAttachment* FB_CARG JProvider::createDatabase(IStatus* user_status, const char*
 
 			switch (options.dpb_sql_dialect)
 			{
-			case 0:
-				// This can be issued by QLI, GDEF and old BDE clients.
-				// In this case assume dialect 1
-				options.dpb_sql_dialect = SQL_DIALECT_V5;
 			case SQL_DIALECT_V5:
 				break;
+			case 0:
 			case SQL_DIALECT_V6:
 				dbb->dbb_flags |= DBB_DB_SQL_dialect_3;
 				break;
diff --git a/src/yvalve/why.cpp b/src/yvalve/why.cpp
index f888df44fd..e77d4dd4ea 100644
--- a/src/yvalve/why.cpp
+++ b/src/yvalve/why.cpp
@@ -1618,6 +1618,14 @@ ISC_STATUS API_ROUTINE isc_create_database(ISC_STATUS* userStatus, USHORT fileLe
 		if (!status.isSuccess())
 			return status[1];
 
+		ClumpletWriter newDpb(ClumpletReader::dpbList, MAX_DPB_SIZE, dpb, dpbLength);
+		if (!newDpb.find(isc_dpb_sql_dialect))
+		{
+			newDpb.insertInt(isc_dpb_sql_dialect, 1);	// legacy behavior in legacy interface
+			dpb = newDpb.getBuffer();
+			dpbLength = newDpb.getBufferLength();
+		}
+
 		YAttachment* attachment = dispatcher->createDatabase(&status, pathName.c_str(),
 			dpbLength, reinterpret_cast<const UCHAR*>(dpb));
 		if (!status.isSuccess())