Is a person's prayer acceptable if his pubic hair is long?

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger. We ask Allaah to exalt his mention as well as that of his family and all his companions.

If someone performs the prayer with its conditions, obligations and pillars, then his prayer is acceptable and valid even if he did not shave his pubic hair. Shaving the pubic hair is not a condition for the validity of the prayer. However, one should know that shaving the pubic hair is one of the acts of Fitrah [natural predisposition]. The Prophet said: "Five are among the Fitrah acts: Circumcision, shaving pubic hair, plucking out armpit hair, clipping one's nails and trimming one's moustache." [Al-Bukhari and Muslim] Ibn Muflih said in Al-Aadaab Ash-Shar'iyyah (the religious etiquettes): 'It is disliked to delay shaving the pubic hair, plucking out armpit hair and trimming one's moustache more than the stated period.'  The stated period is forty days as Imaam Muslim reported that Anas said: "The period that was prescribed for us to trim our moustache, clip our nails, pluck out our armpit hair and shave our pubic hair is forty days." Of course it was the Prophet who determined for them this period of forty days, so it is dislikeable to leave them longer than this period of time.

Allaah knows best.