Well, my 4.5-release CD came. Kernel is dated Feb. 28th 2009. So, I installed and I still get a ral(4) lockup, but now it takes hours to happen. Some of the symptoms that show at first are clients disconnecting. Then finally, the machine gives up and locks itself up. (no response on the serial console.)
I can make the lockup happen faster by transferring a lot of data at a time through ral0. I'm going to take my RT2860 into work, and put it on a 4.5-current machine I have and see if it makes the machine crash as well, to rule out the Soekris being an issue. Tom