[Grew_Some]

International Men in Skirts Day

This is from 1999, but I've heard of related events happening in other years as well.
http://www.angelfire.com/md3/nancyew/MIS_Day.htm

Usually in May I think but I couldn't find much info on it.

At the very bottom of the piece it says May 1st.

Yeah, May 1st, 1999 - not sure it continues as May 1st in subsequent years, but probably. I know someone that may be able to answer that though, so next time I see them, I'll ask.