Income from a foreign pension plan received while a resident of Canada is taxable in Canada irrespective of where it was earned. If you have failed to report such income you can avoid penalties & prosecution by making a voluntary disclosure (tax amnesty application).
"This article provides information of a general nature only. It is only current at the posting date. It is not updated and it may no longer be current. It does not provide legal advice nor can it or should it be relied upon. All tax situations are specific to their facts and will differ from the situations in the articles. If you have specific legal questions you should consult a lawyer."