Sticking to the Woman Speak

In my previous post, I mentioned sexism - or at least stereotypes and 'special treatment'- in Japan.
Don't get me wrong. While I have not quite formed the opinion that Japan is sexist (I definately feel included and respected by my coworkers, for example), I recently learned some interesting tidbits about the culture I see as worth sharing. In addition to all the different levels of formality within the Japanese language (similar to the 'respectful tenses' found in German or Norwegian; feks. bruk av Dem) there are also a slew of words I am simply not allowed to use in Japanese because they are only for men. I think it’s one thing to be respectful and at least try to communicate in the native language, but it is another when I don’t know if I am using the right level of politeness (aim higher here) or even if I am supposed to (or allowed to?) be using the word I learned at all.
The difference in language has got me thinking. When I arrived in Japan, there was a lot of publicity and debate surrounding whether or not females should be able to ascend the royal throne. I know this has a lot to do with tradition, but it makes me wonder what other reasons might have been behind opposing a female heir.... and what else women are not supposed to do here.