Java API: Getting error details through returned Task object

Hello,

Is there a way to gett error details through Task or any other object in Java API?

I tried to use taskType.getError().getMessage() but it only prints "Unable to perform this action. Contact your cloud administrator."

But on vDirector it shows:

could not update: [com.vmware.vcloud.common.model.ServerGroup#a26e600d-4c49-4d7c-8c65-a52dd9c4dd03]
- Violation of UNIQUE KEY constraint 'uk_vm_container_org_vapp_name'. Cannot insert duplicate key in object 'dbo.vm_container'.

How can I get this exact cause of error?

Thanks,

Savita