diff --git a/app/core/processor.py b/app/core/processor.py
index c8d4d28..4089255 100644
--- a/app/core/processor.py
+++ b/app/core/processor.py
@@ -45,6 +45,7 @@ class Processor(Thread):
                     new_comment(msg['data'], msg.get('clientip', ''))
                 elif msg['request'] == 'new_mail':
                     reply_comment_email(msg['data'])
+                    send_delete_command(msg['data'])
                 elif msg['request'] == 'unsubscribe':
                     unsubscribe_reader(msg['data'])
                 elif msg['request'] == 'report':
@@ -114,7 +115,7 @@ def new_comment(data, clientip):
         client_ips[comment.id] = clientip
 
     # send email
-    subject = '%s: [%d:%s]' % (site.name, comment.id, token)
+    subject = 'STACOSYS %s: [%d:%s]' % (site.name, comment.id, token)
     mail(site.admin_email, subject, email_body)
 
     # Reader subscribes to further comments
@@ -146,7 +147,10 @@ def reply_comment_email(data):
         comment = Comment.select().where(Comment.id == comment_id).get()
     except:
         logger.warn('unknown comment %d' % comment_id)
-        send_delete_command(data)
+        return
+
+    if comment.published:
+        logger.warn('ignore already published email. token %d' % comment_id)
         return
 
     if comment.site.token != token:
@@ -157,9 +161,6 @@ def reply_comment_email(data):
         logger.warn('ignore empty email')
         return
 
-    # accept email: request to delete
-    send_delete_command(data)
-
     # safe logic: no answer or unknown answer is a go for publishing
     if message[:2].upper() in ('NO','SP'):
 
diff --git a/app/interface/rmqclient.py b/app/interface/rmqclient.py
index 91857a6..b97cb58 100644
--- a/app/interface/rmqclient.py
+++ b/app/interface/rmqclient.py
@@ -12,14 +12,21 @@ logger = logging.getLogger(__name__)
 
 
 def process_message(chan, method, properties, body):
-    topic = method.routing_key
-    data = json.loads(body)
 
-    if topic == 'mail.message':
-        logger.info('new message => {}'.format(data))
-        processor.enqueue({'request': 'new_mail', 'data': data})
-    else:
-        logger.warn('unsupported message [topic={}]'.format(topic))
+    try:
+        topic = method.routing_key
+        data = json.loads(body)
+
+        if topic == 'mail.message':
+            if "STACOSYS" in data['subject']:
+                logger.info('new message => {}'.format(data))
+                processor.enqueue({'request': 'new_mail', 'data': data})
+            else:
+                logger.info('ignore message => {}'.format(data))
+        else:
+            logger.warn('unsupported message [topic={}]'.format(topic))
+    except:
+        logger.exception('cannot process message')
 
 
 class MessageConsumer(Thread):