commit - 0245a72ab49eb7aa2e6f1a9da709c732df20920b
commit + 3dc1ecc1c89cec6358d207fb114bb79c6153b521
blob - 816988e070d3c40cbfb822f9d7f3ca55851c6871
blob + e070ffbab8e73d1aea731bb5a021b9312d300b8c
--- man/man1/install.1
+++ man/man1/install.1
@@ -36,6 +36,11 @@ builds an HTML version of the manual and installs it i
 .PP
 .I INSTALL
 can safely be repeated to rebuild the system from scratch.
+.PP
+The system uses different threading implementations on Linux 2.6 and
+later kernels than on 2.4 and earlier;
+and on FreeBSD 5 and later kernels than on FreeBSD 4 and earlier.
+Running binaries from one class on another may not work.
 .SH FILES
 .TP
 .B \*9/lib/moveplan9.files