src/de/steamwar/bungeecore/ErrorLogger.java

@@ -71,7 +71,7 @@ public class ErrorLogger extends Handler implements Filter {
 
     @Override
     public void publish(LogRecord record) {
-        if(record.getLevel() != Level.SEVERE)
+        if(record.getLevel() != Level.SEVERE && record.getLevel() != Level.WARNING)
             return;
 
         StringBuilder stacktrace = new StringBuilder(record.getSourceClassName() + "\n" + record.getSourceMethodName());