Get notified when someone add an attachment to a task I've created

Get notified when someone add an attachment to a task I've created

Take this example:
  1. I create a task and assign it to a colleague (as a owner)
  2. the owner add an attachment to the task
  3. I'd like to get notified about the new attachment
Is there a way to get this kind of notification?

I've made some tests and this seems not to be possible.

Thank you