Function pm_unregister has been removed from newer kernels. However, older version of app-laptop/omnibook relies on this. Currently the only unmasked version (20060126) that exists in portage is so old, that it uses pm_unregister. Module loading fails with "omnibook: Unknown symbol pm_unregister".
With ACCEPT_KEYWORDS="~x86", version 20060817 compiles and installs properly. From what I have tested, it seems to work properly (I have tried with HP Omnibook XE3-GF).
Forgot to tell my kernel version, which is gentoo-sources-2.6.18-r3.
Stable for x86. Thanks for the submission...
Tested and verified, works. Very quick reaction, thanks for that!
Had been using this package version for some time :-)