diff --git a/src/cpp/ripple/ValidationCollection.cpp b/src/cpp/ripple/ValidationCollection.cpp
index 0d503748c..e24f3512b 100644
--- a/src/cpp/ripple/ValidationCollection.cpp
+++ b/src/cpp/ripple/ValidationCollection.cpp
@@ -330,3 +330,11 @@ void ValidationCollection::doWrite()
 	}
 	mWriting = false;
 }
+
+void ValidationCollection::sweep()
+{
+	boost::mutex::scoped_lock sl(mValidationLock);
+	mValidations.sweep();
+}
+
+// vim:ts=4
diff --git a/src/cpp/ripple/ValidationCollection.h b/src/cpp/ripple/ValidationCollection.h
index 86398bdb4..e6973886d 100644
--- a/src/cpp/ripple/ValidationCollection.h
+++ b/src/cpp/ripple/ValidationCollection.h
@@ -50,7 +50,7 @@ public:
 
 	void tune(int size, int age);
 	void flush();
-	void sweep() { mValidations.sweep(); }
+	void sweep();
 };
 
 #endif