If rlocate module is loaded before fusion module, the rlocate reserves major 250 and fusion module won't load. Reproducible: Always Loading fusion module before rlocate seems to help.
Well, so load it before rlocate. sys-apps/rlocate is broken w/ 2.6.24 and package.masked anyway.
just add -DFUSION_MAJOR=123 to your CPPFLAGS and rebuild linux-fusion i'll open a report upstream to get them to convert to dynamic major / cdev