So, there's this bug wherein if you click multiple times to respawn, you can press switches with your butt as soon as you spawn. In Deathmatch, if a start is placed in front of an exit - even with your butt facing it - can cause some real BS deaths. (My apologies if this has already been reported.)
Here's a demo, requires tdevil2.wad -
http://www.mediafire.com/download/o5inuj5v7cjlc79/ass_switch_glitch.oddAt about 2 minutes in, you can see I spawn facing away from a blue door, yet it says 'you need a blue key to open this door', showcasing the "pressing stuff with your ass" glitch as I like to call it.
Hope to see this one cleared up!