I remember encountering critics of transsexuality that were gay or gay-sympathetic. I wasn’t able to find anything like that the past half-hour, though.
http://en.wikipedia.org/wiki/Transphobia#Transphobia_in_the_lesbian.2C_gay_and_bisexual_community
http://en.wikipedia.org/wiki/Transphobia#Transphobia_in_the_lesbian.2C_gay_and_bisexual_community