Is an email a legal notice to vacate?

My land lord sent me an email simply stating "I have to give you guys notice to vacate. You guys should make plans to have a another place to live by 9/1/09". After that i have tried calling him and emailing him back with no answer. After a little digging i found out that he is getting foreclosed on. The only reason I am asking is because I have found another place to live but cant move in until 9/15 and need just a little more time.