serial console under ACPI?

I've now basically emptied my /boot/device.hints file, so all the
resources are properly recognized as "at acpi0" as they ought to be.
(Btw., this even solves the problem where the fdc(4) KLD could not be
successfully loaded except from the boot loader due to a resource
allocation problem.)  Anyway, how do I get my serial console back?
sio0 no longer has the required flag 0x10, and my attempt to use

hint.sio.0.at="acpi0"
hint.sio.0.flags="0x30"

as /boot/device.hints still doesn't change this as it appears to be
ignored -- no flags are shown in the sio0 line in dmesg output:

sio0 port 0x3f8-0x3ff irq 4 on acpi0
sio0: type 16550A

So what's the trick to get a true serial console under full ACPI
resouce control?  (Once the kernel is booted, the getty starts OK on
the port, but I'd like to have a true console.)

Using -h in /boot.config, it's no problem whatsoever to operate the
loader itself from the serial console.  Only after the "boot" command,
the system falls into silence until the getty's login prompt appears.

-- 
cheers, J"org               .-.-.   --... ...--   -.. .  DL8DTL

http://www.sax.de/~joerg/                        NIC: JW11-RIPE
Never trust an operating system you don't have sources for. ;-)