Here is an update regarding the way things progress on the v2.1 branch:
o The build system has been deeply revamped, so that we now fully leave the burden of building Xenomai's kernel support to Linux. To this end, the code tree has been reorganized in two major sections, the first one contains the kernel-related sources (ksrc/), the other is hosting the user-space support (src/). Since the user-space portion does not need to know about the kernel sources anymore, several issues have been solved in the same move. All in all, things are way simpler than before, which seems to indicate that we are heading to the right direction. The documentation for the installation process needs to be updated though.
o Also as a matter of build system (and a bit more), v2.1 has been backported to Linux 2.4, starting with the ppc32 support. We rely on Denx's 2_4-devel tree as our 2.4 kernel of reference for this port . A second backport to 2.4/x86 will happen when this combo is I-pipe ready. We are ahead of schedule regarding this backport, since it was initially planned for Q12006, but since we are going to add more supported architectures in the next months, it's better to have a stable build system for that.
o PowerPC-wise (again), we should be close to ready for 2.6.15, since Heikki merged both the 32 and 64-bit trees in a single one.
All other tasks planned are undergoing. For my part, I'm going to fiddle now with ADI's Blackfin for which we already have the required Adeos support, and create the Xenomai port for it. Since this one is uClinux based, we should be able to check that the new build system is ok to host any kind of port sanely.
 http://www.denx.de/en/Software/CVS/ -- Philippe.