In Arabic, "2u5t" can be used euphemistically to refer to a woman, especially in religious language. So "an important sister" can simply mean "an important woman." We sometimes use "2u5taah" ("O' sister"), which incorporates an archaic vocative suffix, to mock the pretentious register of Arabic and the obsession with women's behaviour that ultra-religious Muslims sometimes show. احذري الإيدز يا أختاه ("Beware AIDS O' sister") is a facebook page about sexual health directed towards the gay community, using the term to ironically refer to a male homosexual in this case, rather than an actual woman.
I suggest you mean fundamentalist, instead of ultra-religous. I for example, would consider myself an "ultra" religous Muslim but would not share the same homophobia as a fundamentalist.
Fundamentalism is indeed a major problem of the modern Muslim world but in my opinion should be considered heresy.
It is not a religious action to mock someone else and it is certainly not the behaviour of the Prophet Muhammed SAW.