The Adeos nanokernel [earlier story] now offers symmetric multi-processor support. Karim Yaghmour made the announcement:

"While most of us were at the OLS, Philippe continued hacking on Adeos and has extended the functionality to include SMP support. In light of the discussions I had with many folks at the OLS (the K42 team, Larry, Paul and others), this is a positive step forward to having multiple Linux kernels running on the same hardware."

As explained here, "The purpose of Adeos is to provide a flexible environment for sharing hardware resources among multiple operating systems, or among multiple instances of a single OS." Or, as per the name, Adeos is an Adaptive Domain Environment for Operating Systems. Karim's full announcement follows.

While most of us were at the OLS, Philippe continued hacking on Adeos
and has extended the functionality to include SMP support. In light
of the discussions I had with many folks at the OLS (the K42 team,
Larry, Paul and others), this is a positive step forward to having
multiple Linux kernels running on the same hardware.

The code has been tested on a dual PIII. Of course, further testing
and comments are most welcome. The latest CVS snapshot is available
at: http://savannah.gnu.org/download/adeos/snapshots/

Karim