diff --git a/man2/sigaltstack.2 b/man2/sigaltstack.2
index 38342ef0e..0214315b1 100644
--- a/man2/sigaltstack.2
+++ b/man2/sigaltstack.2
@@ -323,28 +323,38 @@ if (sigaction(SIGSEGV, &sa, NULL) == -1) {
 .EE
 .in
 .SH BUGS
-In the lead up to the development of the Linux 2.4 kernel,
+In the lead up to the release of the Linux 2.4 kernel,
 .\" Linux 2.3.40
-a change was made to allow this system call to accept
+.\" After quite a bit of web and mail archive searching,
+.\" I could not find the patch on any mailing list, and I 
+.\" could find no place where the rationale for this change
+.\" explained -- mtk
+a change was made to allow
+.BR sigaltstack ()
+to accept
 .B SS_ONSTACK
 in
 .IR ss.ss_flags ,
 which results in behavior that is the same as when
 .I ss_flags
-is 0.
+is 0 (i.e., the inclusion of
+.B SS_ONSTACK
+in
+.I ss.ss_flags
+is a no-op).
 On other implementations, and according to POSIX.1,
 .B SS_ONSTACK
 appears only as a reported flag in
 .IR old_ss.ss_flags .
-There is no need ever to specify this flag in
-.IR ss.ss_flags
-(and indeed, doing so decreases portability,
-since some implementations
+On Linux, there is no need ever to specify this flag in
+.IR ss.ss_flags ,
+and indeed doing so should be avoided on portability grounds:
+various other systems
 .\" See the source code of Illumos and FreeBSD, for example.
 give an error if
 .B SS_ONSTACK
 is specified in
-.IR ss.ss_flags ).
+.IR ss.ss_flags .
 .SH SEE ALSO
 .BR execve (2),
 .BR setrlimit (2),