This issue was reported for a while from my FAE.
The kernel of default RHEL 5.3 is v2.6.18........(WTF..)
I personally think that it's a bug of sis190.c driver but I don't have time to dig into the source code.
The NIC MAC address can not be read correctly from EEPROM.
I use sis190.c and mii.c from kernel v2.6.19.7 w/o any modification, and then compile them on RHEL 5.3.
Well, they still taint kernel a bit because no version magic.
But works well (so far..), and my MAC address of SiS 190/191 NIC was now detected.
Use root permission and just # modprobe -rfv sis190
Make mii.ko and sis190.ko by yourself. If you see warnings, forget about it now......
# install -m 644 *.ko /lib/modules/`uname -r`/kernel/drivers/net/
You can make a backup of original mii.ko and sis190.ko if you want.
# depmod -ae
# modprobe -fv sis190
