1 files changed, 1 insertions, 1 deletions
diff --git a/src/java/native/com_libmailcore_IMAPAppendMessageOperation.cpp b/src/java/native/com_libmailcore_IMAPAppendMessageOperation.cpp
index 16da4df2..69b17f08 100644
--- a/src/java/native/com_libmailcore_IMAPAppendMessageOperation.cpp
+++ b/src/java/native/com_libmailcore_IMAPAppendMessageOperation.cpp
@@ -55,7 +55,7 @@ JNIEXPORT void JNICALL Java_com_libmailcore_IMAPAppendMessageOperation_setupNati
     MC_SAFE_RELEASE(callback);
     MC_JAVA_NATIVE_INSTANCE->setImapCallback(NULL);
 
-    jobject javaListener = getObjectField(env, obj, "listener");
+    jobject javaListener = getObjectField(env, obj, "listener", "J");
     if (javaListener != NULL) {
         callback = new JavaIMAPOperationCallback(env, javaListener);
         MC_JAVA_NATIVE_INSTANCE->setImapCallback(callback);