I tested the 20091005 driver again, and after about 20 minutes I lost the HDMI connection. Trust me, 20090907 works, 20091005 has the problem.
root@dm800 ~ # lsmod | egrep "^bcm7401"
bcm7401 3156272 29 - Live 0xc03fd000
root@dm800 ~ # md5sum /lib/modules/2.6.12-5.1-brcmstb-dm800/extra/bcm7401.ko
c324c120bdb3962f3b6ffb3bbd28fa17 /lib/modules/2.6.12-5.1-brcmstb-dm800/extra/bcm7401.ko
root@dm800 ~ # ipkg list_installed | grep dvb-modules
dreambox-dvb-modules - 2.6.12-5.1-brcmstb-dm800-20091005-r0 - Hardware drivers for Dreambox
I use ipkg to upgrade/downgrade the driver, and I reboot the box for it to take effect.