lzop 1.01 can be patched to support multithreading. The patch can be found here: http://lemley.net/lzop_patches/lzop.html I attached the multithreading patch and an ebuild patch. Perhaps this can be added to portage. I've been using patched lzop for a while without problems.
Created attachment 128304 [details, diff] app-arch/lzop-1.01.ebuild patch
Created attachment 128306 [details, diff] lzop parallel source code patch
sorry - I'm not willing to add this unless upstream release lzop with this patch included.