diff --git a/src/com/google/inject/internal/AbstractReferenceCache.java b/src/com/google/inject/internal/AbstractReferenceCache.java
index 9d1ce28..8aa5bdd 100644
--- a/src/com/google/inject/internal/AbstractReferenceCache.java
+++ b/src/com/google/inject/internal/AbstractReferenceCache.java
@@ -144,7 +144,7 @@
       return winningThread;
     }
 
-    V get() {
+    synchronized V get() {
       if (!set) {
         boolean interrupted = waitUntilSet();