A previous post :k3v1n said:
True story: A family friend of mine came to the States in the late 80s as an F1 student. Obtained his degree and even obtained his masters degree but was unable to find a company that was willing to file an H1 for him. He got married to someone from his country and they had two kids. Then sadly, he lost his father but was unable to go home to bury his father because he was no longer lawfully in the States. He is the only son and was not able to go home to comfort his grieving mother and his siblings because he now had the responsibility of being a husband and a father.
This was the straw that broke the camel's back. No one should live like this. No one should have to constantly look over their shoulder and no one should have to choose between burying their parents and providing for their children.He decided to move his family to Canada so that he could be lawful in a good country. About a year later he moved to Canada. (Did not need to go back home) He eventually obtained citizenship and was back in the States over the summer for a friends wedding. After not being able to move about the world freely for 17 yrs, he now breaths freely.
So, for all the naysayers, he did this all from the States and he was waaaay past being legally in the country.
And that is only one example. I know of other people who were in the exact same situation that now reside in Canada. My advise though would be to obtain a lawyer if your case is this complicated.
http://www.canadavisa.com/canada-immigration-discussion-board/-t29896.0.html;msg178017#msg178017