[xmonad] Default Floating Window Criteria (rdesktop)

I'm trying to figure out why XMonad isn't tiling rdesktop by default (and hopefully change it). Whenever I launch rdesktop, the window gets floated. I'm using the default manageHook which, looking at the source, looks like it should only float two programs by default (MPlayer, and mplayer2). The command I'm using to launch rdesktop is 'rdesktop -K -a 32 -x lan -g 1920x1080 $host$'. My xmonad.hs is posted on github if anyone wants to look at it (https://github.com/uxcn/dot-files/blob/master/.xmonad/xmonad.hs). I'm currently using version 0.12. Any help is much appreciated. Thanks in advance. -Jason