On my N900, after closing h-e-n, idle current draw is significantly higher than it was before using hostmode.
As per discussion here --> http://mg.pov.lt/maemo-irclog/%23mae...09-01T23:45:48
it was found that briefly connecting the device to a charger fixes the issue. Another fix that works is to execute /usr/sbin/booston while bme is running, then after about 5 seconds, you kill it and run /usr/sbin/boostoff.
EDIT: it doesn't matter whether bme is running or not. I found that out through updated booston script (see joerg_rw's post below), which stops bme automatically.