GAE Java bug? Intermittent 500 errors enqueuing tasks inside datastore transaction

[Jim]

Hi,

Over the past couple of days I've noticed a large number of 500 errors when my java code attempts to enqueue a task inside a datastore transaction.  

partial stack trace:

com.google.appengine.api.taskqueue.TransactionalTaskException
	at com.google.appengine.api.taskqueue.QueueApiHelper.translateError(QueueApiHelper.java:102)
	at com.google.appengine.api.taskqueue.QueueApiHelper.translateError(QueueApiHelper.java:159)
	at com.google.appengine.api.taskqueue.QueueApiHelper$1.convertException(QueueApiHelper.java:55)
	at com.google.appengine.api.utils.FutureWrapper.get(FutureWrapper.java:96)
	at com.google.appengine.api.utils.FutureWrapper.get(FutureWrapper.java:88)
	at com.google.appengine.api.utils.FutureWrapper.get(FutureWrapper.java:88)
	at com.google.appengine.api.taskqueue.QueueApiHelper.getInternal(QueueApiHelper.java:78)
	at com.google.appengine.api.taskqueue.QueueImpl.add(QueueImpl.java:400)
	at com.h2oanalytics.server.MainMeterPost.doPost(MainMeterPost.java:151)


the offending statement:

        queue.add(withUrl("/default/del_blob").param("key", oldkey).countdownMillis(fourteen_days));

I tried posting this to https://code.google.com/p/googleappengine/issues but haven't received any feedback or help.  Is anyone else seeing similar behavior?  Can someone from Google help me with this?

Jim