I'm not sure that's right. A familiar can use the master's ranks in skills in which the master has ranks. Speak Language has no ranks; instead, you "buy" a language with skill points, the same way you'd buy ranks for a regular skill. Since there are no ranks in Speak Language, there's nothing for the familiar to "share", so familiars (of any type) don't automatically gain languages bought by their masters. After all, if you could do this, why couldn't you do it for any familiar (making the raven's special ability far less special)?
--Axe