now resetting imap errors after successfull job

src/main/java/de/srsoftware/widerhall/data/MailingList.java

@@ -93,6 +93,15 @@ public class MailingList implements MessageHandler, ProblemListener {
         return setFlag(STATE_PUBLIC_ARCHIVE,enabled);
     }
 
+    @Override
+    public void clearProblems() {
+        try {
+            setLastError(null);
+        } catch (SQLException e) {
+            LOG.warn("setLastError(null) failed.");
+        }
+    }
+
     /**
      * create a new ML object int the database
      * @param email

src/main/java/de/srsoftware/widerhall/mail/ImapClient.java

@@ -65,6 +65,7 @@ public class ImapClient {
 
             while (!stopped){
                 handleMessages();
+                problemListener.clearProblems();
                 LOG.debug("Idling.");
                 inbox.idle(true);
             }

src/main/java/de/srsoftware/widerhall/mail/ProblemListener.java

@@ -4,4 +4,6 @@ import javax.mail.MessagingException;
 
 public interface ProblemListener {
     public void onImapException(MessagingException e);
+
+    public void clearProblems();
 }