This system (old Pentium 75 MHz, 24 Mb RAM) works well with 2.4.25+grsecurity or the pure 2.4.26. This is a pure 100% Debian woody, except for the grsec package (1.19 or 2.0, same problem) and the kernel (from kernel.org, as requested by the package maintener).
Applying grsec on a 2.4.26 makes the system unusable : the kernel loads, shows some informations (last one seen : 'Calibrating...', although I can't say if something else appears, it reboots too quickly) and reboots spontaneously. If you know some way to have more logs, tell me...
I've tried to disable totally Grsec, to build everything again from a clean source, I've purged and reinstalled the grsec package, buid it on another (Sarge) box as a last resort, without any change.
The .config is there :
http://www.courtois.cc/perso/config-2.4.26+grsec2
(the grsec part is not important ; as already said it fails even deactivated). This is a the .config of my 2.4.25+grsec with make oldconfig.
Thanks for any help!