You compile crap into the kernel, you are screwed. We have not and will
not change that.
Reiser4 plugins are not for end users to download from amazon.com, they
are for weekend hackers to send me a cool plugin for me to review,
assign a plugin id to, and send to Linus in the next release. Sometimes
being less ambitious works better, and dynamically loaded plugins would
have made the infrastructure too bulky to be fun and fast.