diff --git a/src/java/foundation/pEp/jniadapter/interfaces/AbstractEngineInterface.java b/src/java/foundation/pEp/jniadapter/interfaces/AbstractEngineInterface.java
index 9e3630f..cdfca76 100644
--- a/src/java/foundation/pEp/jniadapter/interfaces/AbstractEngineInterface.java
+++ b/src/java/foundation/pEp/jniadapter/interfaces/AbstractEngineInterface.java
@@ -24,5 +24,7 @@ public interface AbstractEngineInterface {
 
     public void setNeedsFastPollCallback(Sync.NeedsFastPollCallback needsFastPollCallback);
 
+    public void setPassphraseRequiredCallback(Sync.PassphraseRequiredCallback passphraseRequiredCallback);
+
     public Message incomingMessageFromPGPText(String pgpText, Message.EncFormat encFormat);
 }