diff --git a/src/java_lang_Class.cc b/src/java_lang_Class.cc
index 6cf7a2c..d16524b 100644
--- a/src/java_lang_Class.cc
+++ b/src/java_lang_Class.cc
@@ -132,6 +132,7 @@
 }
 
 static jobjectArray Class_getDeclaredFields(JNIEnv* env, jclass javaClass, jboolean publicOnly) {
+  ScopedThreadStateChange tsc(Thread::Current(), Thread::kRunnable);
   Class* c = DecodeClass(env, javaClass);
   if (c == NULL) {
     return NULL;