This plugin saved me!
I imported my blogger blog to wordpress, over than 650 posts and i changed the permalink structure in wordpress to take advantage of SEO and this plugin saved all those over 650 permalinks!
i should've found this plugin before cause now i have over 650 "404 errors" in google webmaster tools, but hopefully this is not for long.
You saved me 2 years of hard work :)
Thank you so much!