diff --git a/man2/sigaction.2 b/man2/sigaction.2
index 48cf12174..bf5d2bb29 100644
--- a/man2/sigaction.2
+++ b/man2/sigaction.2
@@ -40,7 +40,7 @@
 .\" 2005-09-15, mtk, split sigpending(), sigprocmask(), sigsuspend()
 .\"	out of this page into separate pages.
 .\"
-.TH SIGACTION 2 2008-10-04 "Linux" "Linux Programmer's Manual"
+.TH SIGACTION 2 2008-10-17 "Linux" "Linux Programmer's Manual"
 .SH NAME
 sigaction \- examine and change a signal action
 .SH SYNOPSIS
@@ -142,8 +142,10 @@ as its second argument and a pointer to a
 (cast to \fIvoid\ *\fP) as its third argument.
 .PP
 .I sa_mask
-gives a mask of signals which should be blocked during execution of
-the signal handler.
+specifies a mask of signals which should be blocked
+(i.e., added to the signal mask of the thread in which
+the signal handler is invoked)
+during execution of the signal handler.
 In addition, the signal which triggered the handler
 will be blocked, unless the
 .B SA_NODEFER