diff --git a/ascon.c b/ascon.c
index 799417dc..fefb8408 100644
--- a/ascon.c
+++ b/ascon.c
@@ -180,7 +180,7 @@ int AsconReadGarbage(int fd)
       if (l > 0) {
         /* swallow */
         garbage[l] = '\0';
-        printf("(((%s)))\n", garbage);
+        /* printf("(((%s)))\n", garbage); */
         result += l;
       } else if (l == 0) {
         errno = ECONNRESET;
diff --git a/devser.c b/devser.c
index a2045fca..fc5d33f2 100644
--- a/devser.c
+++ b/devser.c
@@ -1,3 +1,4 @@
+#include <stdio.h>
 #include <math.h>
 #include "ascon.h"
 #include "devser.h"
@@ -57,7 +58,7 @@ static void DevFreeActionList(DevAction * actions)
   }
 }
 
-static double nextTime(double last,
+static double nextTime(double due,
                        double lastInterval,
                        double now,
                        double interval) {
@@ -66,12 +67,12 @@ static double nextTime(double last,
    * following rules:
    * (1) result > now
    * (2) result is a multiple of interval
-   * (3) result > last + min(lastInterval,interval) * 0.99
+   * (3) result >= due OR result >= due - lastInterval + interval
    */
   if (interval > lastInterval) {
-    base = last + lastInterval * 0.99;
+    base = due - lastInterval * 0.01;
   } else {
-    base = last + interval * 0.99;
+    base = due - lastInterval + interval * 0.99;
   }
   if (now > base) {
     base = now;
@@ -79,6 +80,7 @@ static double nextTime(double last,
   return (floor(base / interval) + 1) * interval;
 }
 
+
 static DevAction *DevNextAction(DevSer * devser)
 {
 /* the action queue is primarily ordered by priority (high prioirty first),
@@ -104,8 +106,7 @@ static DevAction *DevNextAction(DevSer * devser)
           action->timeDue = now;
         } else {
           /* increase timeDue according to interval */
-          action->timeDue = nextTime(action->timeDue, action->interval,
-            now, action->interval);
+          action->timeDue = nextTime(0, 0, now, action->interval);
         }
         prio = action->prio;
         
@@ -270,7 +271,7 @@ int DevSchedule(DevSer * devser, void *actionData,
   DevAction **ptr2prev;
   DevAction **ptr2insertPos = NULL;
   int ret;
-  
+
   if (prio <= NullPRIO) {
     prio = NullPRIO + 1;
   }
@@ -280,7 +281,7 @@ int DevSchedule(DevSer * devser, void *actionData,
   
   for (ptr2prev = &devser->actions, action = devser->actions;
        action != NULL;
-       ptr2prev = &action->next, action = action->next) {
+       action = action->next) {
     if (action->prio < prio && ptr2insertPos == NULL) {
       ptr2insertPos = ptr2prev;
     }
@@ -292,21 +293,28 @@ int DevSchedule(DevSer * devser, void *actionData,
         && matchFunc(actionData, action->data)) {
       if (prio == action->prio && interval < 0) {
         /* do not move an action with equal prio */
-        killFunc(actionData);
-        return 0;
+        if (killFunc) {
+          killFunc(actionData);
+        }
+        return 0; /* not queued */
       }
       /* remove action from list */
       *ptr2prev = action->next;
       foundAction = action;
+    } else {
+      ptr2prev = &action->next;
     }
   }
   
-  /* create if needed */
   if (foundAction != NULL) {
+    /* a similar action was found */
     action = foundAction;
+    if (killFunc) {
+      killFunc(actionData);
+    }
     ret = 0;
-    killFunc(actionData);
   } else {
+    /* create if needed */
     action = calloc(1, sizeof(*action));
     assert(action);
     action->data = actionData;
@@ -335,7 +343,7 @@ int DevSchedule(DevSer * devser, void *actionData,
     }
     action->interval = interval;
   }
-  return ret;
+  return ret; /* when 0, actionData was killed */
 }
 
 int DevQueue(DevSer * devser, void *actionData, DevPrio prio,
diff --git a/devser.h b/devser.h
index 39ffa54d..9de4d7dc 100644
--- a/devser.h
+++ b/devser.h
@@ -77,7 +77,7 @@ void DevDisconnect(DevSer * devser);
  *    after the action has finished, i.e. when hdl returned NULL) 
  *    or NULL if no kill function is needed.
  * \return 1 when this was a new action, 0 when an action was overwritten
- *        in the second case the actionData's kill Function is called
+ *        in the second case the actionData's kill Function is immediately called
  */
 int DevQueue(DevSer * devser, void *actionData, DevPrio prio,
              DevActionHandler * hdl, DevActionMatch * matchFunc,
@@ -95,7 +95,7 @@ int DevQueue(DevSer * devser, void *actionData, DevPrio prio,
  * \param matchFunc a match function with two arguments of the same type
  * \param killFunc the action data kill function or NULL if no kill function is needed.
  * \return 1 when this was a new action, 0 when an action was overwritten
- *        in the second case the actionData's kill Function is called
+ *        in the second case the actionData's kill Function is immediately called
  */
 int DevSchedule(DevSer * devser, void *actionData,
                 DevPrio prio, double interval,
diff --git a/scriptcontext.c b/scriptcontext.c
index 05a6635e..64d503cc 100644
--- a/scriptcontext.c
+++ b/scriptcontext.c
@@ -1008,13 +1008,8 @@ void SctQueueNode(SctController * controller, Hdb * node,
   data->conCtx = NULL;
   data->answered = 1;
   
-  if (!DevQueue(data->controller->devser, data, prio,
-                SctWriteHandler, SctMatch, SctKillData)) {
-    if (data->name != NULL) {
-      free(data->name);
-    }
-    free(data);
-  } else {
+  if (DevQueue(data->controller->devser, data, prio,
+               SctWriteHandler, SctMatch, SctKillData)) {
     if (con != NULL) {
       data->conCtx = SCCopyConnection(con);
     }