serial troubles

[Ivan Baidakov <ivan.baidakov@xxxxxxxxxxxxxxxx>]

	DF always sends messages like following, when I have an internet connection via my external modem connected to COM1..
sio0: 1 more silo overflow (total 1)
sio0: 1 more silo overflow (total 2)
sio0: 1 more silo overflow (total 3)
sio0: 1 more silo overflow (total 4)
sio0: 1 more silo overflow (total 5)
	I mean, it does not reflect on connection, but it is annoying...

dmesg:
Copyright (c) 2003, 2004 The DragonFly Project.
Copyright (c) 1992-2003 The FreeBSD Project.
Copyright (c) 1979, 1980, 1983, 1986, 1988, 1989, 1991, 1992, 1993, 1994
	The Regents of the University of California. All rights reserved.
DragonFly 1.0A-RELEASE #1: Wed Jul 14 18:55:41 GMT 2004
    root@:/usr/obj/usr/src/sys/GENERIC
CPU: AMD Athlon(tm)  (1252.85-MHz 686-class CPU)
  Origin = "AuthenticAMD"  Id = 0x680  Stepping = 0
  Features=0x383f9ff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,MMX,FXSR,SSE>
  AMD Features=0xc0400000<AMIE,DSP,3DNow!>
real memory  = 259981312 (253888K bytes)
avail memory = 241487872 (235828K bytes)
Preloaded elf kernel "/kernel" at 0xc063f000.
Preloaded elf module "/modules/snd_t4dwave.ko" at 0xc063f1e8.
Preloaded elf module "/modules/snd_pcm.ko" at 0xc063f294.
Preloaded elf module "/modules/acpi.ko" at 0xc063f33c.
Pentium Pro MTRR support enabled
md0: Malloc disk
pcibios: BIOS version 2.10
Using $PIR table, 6 entries at 0xc00fde70
npx0: <math processor> on motherboard
npx0: INT 16 interface
Using MMX optimized bcopy/copyin/copyout
acpi0: <AWARD AWRDACPI> on motherboard
installed MI handler for int 9
acpi0: Power Button (fixed)
cpu0: <ACPI CPU (3 Cx states)> on acpi0
acpi_tz0: <Thermal Zone> on acpi0
acpi_button0: <Power Button> on acpi0
acpi_button1: <Sleep Button> on acpi0
pcib1: <ACPI Host-PCI bridge> port 0x290-0x297,0x50c0-0x50ff,0x5000-0x50bf,0x480-0x48f,0xcf8-0xcff on acpi0
pcib1: couldn't read bus number from cfg space
pcib1: trying bus number 1
pci1: <ACPI PCI bus> on pcib1
pci1: <SiS model 6300 VGA-compatible display device> at 0.0
pcib0: <Host to PCI bridge> at pcibus 0 on motherboard
pci0: <PCI bus> on pcib0
agp0: <SiS 730 host to AGP bridge> mem 0xc0000000-0xcfffffff at device 0.0 on pci0
atapci0: <SiS 5591 ATA100 controller> port 0x4000-0x400f at device 0.1 on pci0
ata0: at 0x1f0 irq 14 on atapci0
installed MI handler for int 14
ata1: at 0x170 irq 15 on atapci0
installed MI handler for int 15
isab0: <SiS 85c503 PCI-ISA bridge> at device 1.0 on pci0
isa0: <ISA bus> on isab0
ohci0: <SiS 5571 USB controller> mem 0xd9100000-0xd9100fff irq 5 at device 1.2 on pci0
installed MI handler for int 5
usb0: OHCI version 1.0, legacy support
usb0: SMM does not respond, resetting
usb0: <SiS 5571 USB controller> on ohci0
usb0: USB revision 1.0
uhub0: SiS OHCI root hub, class 9/0, rev 1.00/1.00, addr 1
uhub0: 3 ports with 3 removable, self powered
ohci1: <SiS 5571 USB controller> mem 0xd9101000-0xd9101fff irq 5 at device 1.3 on pci0
usb1: OHCI version 1.0, legacy support
usb1: SMM does not respond, resetting
usb1: <SiS 5571 USB controller> on ohci1
usb1: USB revision 1.0
uhub1: SiS OHCI root hub, class 9/0, rev 1.00/1.00, addr 1
uhub1: 3 ports with 3 removable, self powered
pcm0: <SiS 7018> port 0xe000-0xe0ff mem 0xd9103000-0xd9103fff irq 11 at device 1.4 on pci0
pcm0: <Avance Logic ALC101 AC97 Codec>
installed MI handler for int 11
pcib2: <PCI to PCI bridge (vendor=1039 device=0001)> at device 2.0 on pci0
pci2: <PCI bus> on pcib2
pci2: <SiS model 6300 VGA-compatible display device> at 0.0
rl0: <RealTek 8139 10/100BaseTX> port 0xe400-0xe4ff mem 0xd9102000-0xd91020ff irq 11 at device 9.0 on pci0
miibus0: <MII bus> on rl0
rlphy0: <RealTek internal media interface> on miibus0
rlphy0:  10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, auto
rl0: MAC address: 00:00:11:00:09:56
orm0: <Option ROMs> at iomem 0xc0000-0xcbfff,0xcc000-0xcffff on isa0
pmtimer0 on isa0
fdc0: <NEC 72065B or clone> at port 0x3f0-0x3f5,0x3f7 irq 6 drq 2 on isa0
installed MI handler for int 6
atkbdc0: <Keyboard controller (i8042)> at port 0x60,0x64 on isa0
atkbd0: <AT Keyboard> flags 0x1 irq 1 on atkbdc0
kbd0 at atkbd0
installed MI handler for int 1
psm0: <PS/2 Mouse> irq 12 on atkbdc0
installed MI handler for int 12
psm0: model NetMouse/NetScroll Optical, device ID 0
vga0: <Generic ISA VGA> at port 0x3c0-0x3df iomem 0xa0000-0xbffff on isa0
sc0: <System console> at flags 0x100 on isa0
sc0: VGA <16 virtual consoles, flags=0x300>
sio0 at port 0x3f8-0x3ff irq 4 flags 0x10 on isa0
sio0: type 16550A
installed MI handler for int 4
sio1: can't drain, serial port might not exist, disabling
ppc0: <Parallel port> at port 0x378-0x37f irq 7 on isa0
ppc0: Generic chipset (ECP/PS2/NIBBLE) in COMPATIBLE mode
ppc0: FIFO with 16/16/16 bytes threshold
ppbus0: <Parallel port bus> on ppc0
plip0: <PLIP network interface> on ppbus0
lpt0: <Printer> on ppbus0
lpt0: Interrupt-driven port
ppi0: <Parallel I/O> on ppbus0
installed MI handler for int 7
installed MI handler for int 0
ad0: 76319MB <ST380011A> [155061/16/63] at ata0-master UDMA100
Mounting root from ufs:/dev/ad0s3a