I do not have any experience with this particular card, perhaps someone else here does though. But from what I could determine it would use the Lance driver. Most all ethernet drivers at least originate from Donald Becker. So you might check his site for some information.
http://www.scyld.com/network/
The source file in the kernel source has not been updated since last September. So it could be a kernel issue.
But you might try building the driver into the kernel if you are using modules. Also, if module, then you could try to stop the adapter and unload the module, then attempt to warm boot. Something like:
ifconfig eth0 down
rmmod lance
Use the "lsmod" command to view the modules loaded to see if anything else is active on the module if needed. Perhaps unloading the module would reset the ports so that it can be loaded again after the reboot.
Good Luck.