guh, after much fiddling, i figured out what was happening... the taskbar area's width was set too high somehow and it resulted in the taskbar running into the tasktray by the size of one quicklaunch icon, so i changed
TaskBarWidth $ResolutionX-TaskBarX-SystrayWidth-TimeWidth$

in taskbar.rc to

TaskBarWidth $ResolutionX-TaskBarX-SystrayWidth-TimeWidth-54$

which seems to work