comconsole trouble on ASUS A8VE-deluxe

[Arno J. Klaassen]

Hello,

I can't seem to get comconsole work on an ASUS A8VE-Deluxe MB :

 - I get the boot-menu, can escape to loader prompt
   and type, but no output once kernel starts booting

 - I tried (almost) all possible combinations of hint.sio.0.flags
   but no change, though 0x00008 to recover sooner from lost output
   interrupts, *sometimes* gives blurbs of output

 - even pulling out the graphics card does not help

 - when in multi-user a good old "kermit" over cuad0 works OK

 - these are the relevant dmesg lines :

   sio0: configured irq 4 not in bitmap of probed irqs 0
   sio0: port may not be enabled
   sio0: irq maps: 0 0 0 0
   sio0: <16550A-compatible COM port> port 0x3f8-0x3ff irq 4 flags 0x30038 on acpi0
   sio0: type ST16650A, console
   ioapic0: routing intpin 4 (ISA IRQ 4) to vector 55

Anyone an idea of what to try next?
I tried uart(4) iso sio(4) and hint.uart.0.flags="0x10", no change,
but I'm not quite sure this is supposed to work on amd64-stable.

Thanx a lot in advance.

Arno