The historical Buddha's most famous statements on women came about when his stepmother and aunt, Maha Pajapati Gotami, asked to join the Sangha and become a nun. The Buddha initially refused her request. Eventually he relented, but in doing so he made conditions and a prediction that remain controversial to this day. ... Pajapati approached her stepson and asked to be received into the Sangha. The Buddha said no. Still determined, Pajapati and 500 women followers cut off their hair, dressed themselves in patched monk's robes, and set out on foot to follow the traveling Buddha.
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Ananda sat at the Buddha's side and argued on behalf of the ordination of women. The Buddha continued to refuse the request. Finally, Ananda asked if there was any reason women could not realize enlightenment and enter Nirvana as well as men.
The Buddha admitted there was no reason a woman could not be enlightened. "Women, Ananda, having gone forth are able to realize the fruit of stream-attainment or the fruit of once-returning or the fruit of non-returning or arahantship," he said.
Ananda had made his point, and the Buddha relented. Pajapati and her 500 followers would be the first Buddhist nuns. But he predicted that allowing women into the Sangha would cause his teachings to survive only half as long - 500 years instead of a 1,000.
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Further, according to the canonical texts, before the Buddha allowed Pajapati into the Sangha, she had to agree to eight Garudhammas, or grave rules, not required of men. These are:
A Bhikkuni (nun) even if she was in the Order for 100 years must respect a Bhikkhu (monk) even of a day's standing.
A Bhikkuni must reside within 6 hours of traveling distance from the monastery where Bhikkhus reside for advice.
On Observance days a Bhikkhuni should consult the Bhikkhus.
A Bhikkhuni must spend rainy season retreats under the orders of both Bhikhus and Bhikkhunis.
A Bhikkhuni must live her life by both the orders.
A Bhikkhuni must on two years obtain the higher ordination (Upasampatha) by both Orders.
A Bhikkhuni cannot scold a Bhikkhu.
A Bhikkhuni cannot advise a Bhikkhu.
http://buddhism.about.com/od/buddhisthi ... twomen.htm