I would like to suggest a possible answer to the apparent stirah between the rambam and the gemara in Baba Basra. One very simple answer is the gemara and the Rambam are talking about two very different types of nevuos. The gemara in Baba Basra that is being referred to goes on to mention an example of nevuah which is given to fools. The nevuah mentioned there is a simple message about whomever signs his name tevyomi can be the next leader in Masa Mechasya. The message was given over in the marketplace. I would compare this to like a bas kol --- Hashem just wanted to get the message across to Mar Bar Rav Ashi so he would go to Masa Mechasya. I imagine this is not the type of nevuah the rambam is reffering to when he says it's only for the wise. Perhaps the Rambam is referring to the nevuos that come only when one is close to Hashem where Hashem gives messages that affect bnai yisrael and Hashem gives it to a great prophet to understand and deliver properly. It is not merely Hashem putting some words in someone's mouth (as is the case by the fool where I doubt he even understood what he was saying.)
Anyways, I understand you may not be interested in posting this but I am really interested in your opinion and I would really appreciate if you would email me what you think of my answer. (please delete my email if you decide to post this message.)
commanderq3 - hotmail - com
Thanks A Lot and I really enjoy your site.