Error Time in Talend 5.1.3 Open Studio - "Execution failed :generationManager is not initialized by the perljet/javajet!"

Hello every one,
It has given me a learning experience with Talend 5.1.3...

Yesterday(3rd feb 2014) every thing(Talend project jobs) working fine .. I have developed few jobs and executed successfully..

Today I have  executed the same jobs again and I received an error saying
 "Execution failed :generationManager is not initialized by the perljet/javajet!"

I had done a small googling and tried the tip from here

What I did to work properly..
1) What ever the newly created jobs(I've 2 jobs for testing purpose for a functionality)  created yesterday , I deactivated them.
2) Deleted org folder from \.JETEmitters\src folder and then tried to execute the job. I got null pointer exception.
3) Restored the org folder and executed required job.. it is working now..


What I understand from this error is :
What ever the jobs we create, we need to maintain all the information used by those jobs..
In my case I've created a job for testing purpose and taken a metadata file... later I removed metadata file and kept the job as it is.. so when I execute the other talend jobs.. the project was looking for all the resources available for the remaining jobs as well. and caused for the error.