Sure, me, make myself sleep when I have a problem like this.

I know what it is, damn simple: the /dev/shm directory needs to exist before you can mount on it. Apparently, by default, that early in the boot it doesn't.

The reason I didn't notice is that 2 days ago on my dev. N900 I mkdir'ed that directory from inside the @boot console. Since then it hasn't disappeared. But I guess normally is does go away between reboots? Really odd to me. I am done digging for a few days. The solution is right there, but I don't want to just add mkdir and rmdir calls to the code without knowing if that's the 'right way'. I want to know how/why /dev/shm normally gets created and then disappears - and why manually making it at book kept it safe from getting killed through the reboots. Is it some sort of virtual directory that isn't actually written to the flash, normally? If so, I'd rather figure out how to do it properly that way and not chip away at the NAND flash with a a pair of mkdir/rmdir calls every time rdmod runs.

Okay, NOW sleep.