SPARC64 has broken strace/ptrace handling code in 2.6.15. This is already fixed upstream in git, fix by Luis F. Ortiz and Richard Mortimer. http://www.kernel.org/git/?p=linux/kernel/git/davem/sparc-2.6.git;a=commit;h=695ca07bf1036091eff2f11d2fe5f1585c2ac8c8
Created attachment 76757 [details, diff] strace/ptrace fix for sparc64
Fixed in gentoo-sources-2.6.15-r1