Processing rule exists but can't be read

I’ve made a service in developer that returns the details of all processing rules that correspond to some filters on the name fo the processing rule.
I somehow get the ruleID, then use the service “getRule” to get the rule.
Everthing works fine, except that after an indefinite number of runs of this service I encountered a bug: the processing rule I used to test my service started to bug:

  • I could see it but couldn’t edit it in TN Console (double-clicking or selecting the “edit” option just didn’t do anything)
  • The “attributeCondition” of the output of the service “getRule”, which is supposed to be a List of List of String, contained only one id, which was correct, but it didn’t contain everything else (OK if you understand this explanation either you’re a god or I am or you already know what I’m talking about)

The processing rule became operationnal again after I reloaded the WmTN package (probably because it reloaded the TN informations from the database).

Is there a reason and/or a solution besides reloading from the database?

PS: We use TN and developer 6.1

Well I don’t think this will help you but it does help me:
The service messes the processing rules only in step-by-step mode. I made a web-app that calls the service, and after an important number of runs, I still see no problem.
So the problem could come from the step-by-step mode, is this a thread-related problem?