I am also asked to fill in 'Details of Government Employment' for both my parents. My father in law is retired Govt employee but mother in law is still in service and they were asked to send their Govt employment history again.
Parents Country - India
Visa office - Ottawa
They sent one form to fill in the details but it doesn't have any IMM number on it, looks like a simple excel template asking start/end dates, position, title, duties, supervisor name, department and location.
Well, the original application form (IMM5669) itself had those details but I think what they want now is in more details (especially on unit/department and duties).