The Bible never says Sodom and Gomorrah were destroyed because of homosexuality. There is one quote in the Book of Jude that says they went after "strange flesh" but that doesn't really imply homosexuality. If I remember correctly, the word for strange was more akin to "other" and in that sense, the flesh of woman would be certainly stranger than that of a man, because of the difference of genders.
But nowhere does God say, "Them Sodomites is bein gay. Gonna burn em up, yessir!"
If you can find any passage that says they were condemned for having homosexual relations with each other, then by all means prove me wrong. But it ain't gonna happen!
They were destoryed because of their gross amount of sin. And it does say somewhere in the Bible that God sees homosexuality as an abomantion.