10 years after the end of the employment contract : Simple retirement... or unfair dismissal ?

Can a simple retirement, even 10 years later, be reclassified as an unfair dismissal ?

This is a typical exemple of French law regarding the re-qualification of a "act of deed" (the employee considers that his 'voluntary' departure is due to the wrongful behaviors of the employer) in a dismissal exclusively based on the fault of the employer.