Pagan prisoners will be allowed four days off work next year for festivals which celebrate lactating sheep and promiscuity.
The Prison Service will allow inmates who follow the religion to choose four days from the eight recognised Pagan holidays when they must be excused from work.
Arrangements could also be made for inmates to be served traditional food, which includes roast boar and non-alcoholic honey mead.
The prison instruction, Religious Festival Dates for 2011, includes similar provisions for those who follow other religions, including Christians, Muslims and Buddhists.
"The Prison Service is committed to ensuring that prisoners from all religious faiths are given the opportunity and facilities to practise
their religion," it read.
"This instruction provides information to ensure staff are aware of the key religious dates, and their requirements, for the main faiths.
"Some of these festivals require prisoners to be excused from work or to fast."
Governors and co-ordinating chaplains "must ensure equitable provision across the faiths in terms of food for religious festivals", the instruction added.
"The cost of food must be proportionate to the number of prisoners involved and consistent with the cost per prisoner incurred in other religious festivals for other faiths."
The Pagan festivals include Imbolc, the "festival of the lactating sheep", on February 1, which marks the beginning of spring, and Beltane, on May 1, which marks the arrival of summer, and in Old Celtic traditions was a time of unabashed sexuality and promiscuity.
Others include the spring equinox on March 20, the midsummer solstice on June 21, Lammas or Lughnasadh - the first harvest of the year - on August 1, the autumn equinox on September 23, Samhain - the third harvest which marks the end of summer - on October 31, and Yule, the winter solstice, on December 21.