diff --git a/uppsrc/Core/Mt.cpp b/uppsrc/Core/Mt.cpp
index 748a57c68..b06ef455a 100644
--- a/uppsrc/Core/Mt.cpp
+++ b/uppsrc/Core/Mt.cpp
@@ -637,7 +637,7 @@ RWMutex::~RWMutex()
 	pthread_rwlock_destroy(rwlock);
 }
 
-void ConditionVariable::Wait(Mutex& m, int timeout_ms)
+bool ConditionVariable::Wait(Mutex& m, int timeout_ms)
 {
 	struct timespec until;
 	clock_gettime(CLOCK_REALTIME, &until);
@@ -648,7 +648,7 @@ void ConditionVariable::Wait(Mutex& m, int timeout_ms)
 	until.tv_sec += until.tv_nsec / 1000000000;
 	until.tv_nsec %= 1000000000;
 
-	return pthread_cond_timedwait(cv, m.mutex, &until);
+	return pthread_cond_timedwait(cv, m.mutex, &until) == 0;
 }
 
 #ifdef PLATFORM_OSX
diff --git a/uppsrc/Core/Mt.h b/uppsrc/Core/Mt.h
index 9600cf75e..216902ed6 100644
--- a/uppsrc/Core/Mt.h
+++ b/uppsrc/Core/Mt.h
@@ -205,7 +205,7 @@ class ConditionVariable {
 	
 public:
 	void Wait(Mutex& m);
-	void Wait(Mutex& m, int timeout_ms);
+	bool Wait(Mutex& m, int timeout_ms);
 	void Signal();
 	void Broadcast();
 	
@@ -262,7 +262,7 @@ class ConditionVariable {
 	
 public:
 	void Wait(Mutex& m)  { pthread_cond_wait(cv, m.mutex); }
-	void Wait(Mutex& m, int timeout_ms);
+	bool Wait(Mutex& m, int timeout_ms);
 
 	void Signal()        { pthread_cond_signal(cv); }
 	void Broadcast()     { pthread_cond_broadcast(cv); }