diff --git a/src/jrd/extds/ExtDS.cpp b/src/jrd/extds/ExtDS.cpp
index c9cd0651c2..3d939813b0 100644
--- a/src/jrd/extds/ExtDS.cpp
+++ b/src/jrd/extds/ExtDS.cpp
@@ -54,7 +54,7 @@ namespace EDS {
 GlobalPtr<Manager> Manager::manager;
 Mutex Manager::m_mutex;
 Provider* Manager::m_providers = NULL;
-bool Manager::m_initialized = false;
+volatile bool Manager::m_initialized = false;
 
 Manager::Manager(MemoryPool& pool) :
 	PermanentStorage(pool)
diff --git a/src/jrd/extds/ExtDS.h b/src/jrd/extds/ExtDS.h
index 9028ae3c4e..dad7b8229e 100644
--- a/src/jrd/extds/ExtDS.h
+++ b/src/jrd/extds/ExtDS.h
@@ -77,7 +77,7 @@ private:
 	static Firebird::GlobalPtr<Manager> manager;
 	static Firebird::Mutex m_mutex;
 	static Provider* m_providers;
-	static bool m_initialized;
+	static volatile bool m_initialized;
 };