here's my situation: i've got three computers running in my network, one is an old imac g3 233 which is print- web- and fileserver, running debian testing with a 2.6.18 kernel. the others are a g5 desktop and a compaq armada laptop which runs kubuntu 6.10. now i'm working for over two weeks on the problem that i can normally download from the imac to my laptop over ftp, sambe with a speed from around 800 kb/s. this is ok, because the external harddisk i'm downloading from is connected via usb 1.0 to the imac.
but when i try to download directly to the g5, the speed is somewhere around 20 kb/s and it takes me days to copy the three gigs i need...
same files downloaded from the laptop to the g5 did not cause any trouble, samba and ftp are working...
after a fresh installation on the imac the problem was stil here, so changed all the cables... still the same.
i tried to set the speed and duplex manually to 100 / full duplex with mii-tool, eth-tool and ifconfig, but it looks as the driver wouldn't support this command, i just get error messages like:

iMac:~# mii-tool -v -F 100baseTx-FD
SIOCGMIIPHY on 'eth0' failed: Operation not supported
no MII interfaces found
iMac:~#

The funny thing is that everything else is working fine, even the webserver.
Thx for any help...