+ARCHITECTURES SUPPORTED
+-----------------------
+
+Currently, x86 (only P6+), x86 64, PowerPC 32/64 and S390 are
+supported. The current use of sys_futex() makes it Linux-dependent, although
+this portability limitation might go away in a near future by using the pthread
+cond vars. Also, the restriction against i386, i486 and Pentium might go away if
+we integrate some of glibc runtime CPU-detection tests.
+