From the Catholic Church’s website (entire discussion of the issue within quotes)

“The Same-Sex-Union Issue
The Nigerian Senate last week voted to outlaw same-sex unions and all such public manifestations to the great relief of most Nigerians. We note that the Senate took this courageous and hope-inducing decision in the face of considerable internal and international pressure to do the exact opposite. Nigeria has in fact since then been directly asked by some Western countries to reverse this decision or forfeit certain aids and support. We wish to strongly support the prohibition of same-sex union as an expression both of our cultural values as Nigerians and our religious belief as Christians. Far from being a denial of the fundamental right of some Nigerians who would engage in it, such a prohibition protects our society from the usurpation of its right to moral health and cultural decency. We declare that no country has the right to impose on another such conditions as are likely to upset its common cultural and societal values just to satisfy the exotic desires and tendencies of a few.”

This statement was issued in an official communique of the Roman Catholic Church on the website of the Nigerian Catholics Bishops Conference and signed by Archbishop Job of Ibadan and Bishop Martins of Nigeria. It was issued the same week as the Nigerian Senate took up debate on the legislation you referenced. This direct and public support of the legislation that seeks to jail all Gay persons in the nation for the ‘crime’ of existing, petitioning their government for redress, assembling or associating (even in private), conducting religious ceremonies, or enjoying freedom of press or speech is quite shocking. This bill could make the Episcopal Church illegal, or even a meeting of Courage.

Far from being a quiet ‘throwaway statement’, the Roman Catholic Church’s public support for this legislation was covered by the mass media in Nigeria. The Daily Trust (via All Africa) reported this support on 13 December 2011.

There is not a difference between the Catholic Church in Nigeria and the USA. Same liturgy, same leadership. How are the actions of the Roman Catholic Church consistent with Catechism 2358? Why are the US Conference of Catholic Bishops still in communion with the Nigerian Conference of Catholic Bishops. Why hasn’t the Vatican gotten involved here, seeing as they apparently micromanage political events? Why hasn’t the Vatican condemned Nigerian Senator David Mark (a Catholic who is apparently a supporter of the legislation) while condemning American Catholics who support same sex rights.