sio problem in -current (COM1)

I'm having a problem with -current on a ProLiant BL10e blade server.  On
the blade server, we use a serial console on sio0/COM1.  This works
perfectly with 4.8, but for some reason, the sio driver doesn't see COM1
at all, and assigns COM2 resources to sio0.  Any pointers to where I
should look would be greatly appreciated.

I've attached dmesg output for 4.8 and -current on this blade.

Thanks,
John
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John Cagle     john.cagle_at_hp.com
Principal Member Technical Staff
   Industry Standard Servers
    Hewlett-Packard Company