Hi Gerard, 

Thanks for the explanation. The kernel we're running
has been patched for better Oracle performance. The
patch --attached to this mail-- effects SHMMAX, SHMMNI, 
SHMSEG, SEMMNI, SEMMSL, SEMMNS, SEMUME, SEMMNU, and SEMMAP; 
and I just saw a comment in include/asm-i386/shmparam.h 
saying not to touch the default SHMMAX because people 
depend on it.

Maybe this explains the mystery?

Cheers,

Berkan