+@vindex message-prune-recipient-rules
+@code{message-prune-recipient-rules} \e$B$O!"9-$$JVEz$r$9$k$H$-$KFCDj$N%"%I\e(B
+\e$B%l%9$r<h$j=|$/$?$a$K;H$$$^$9!#=EJ#$7$?%"%I%l%9$N$h$&$J$b$N$r:o=|$9$k$?$a\e(B
+\e$B$K;H$&$H$$$&0UL#$G$9!#$3$l$O%j%9%H$N%j%9%H$G$9!#:G=i$NMWAG$O!"$"$k5,B'$r\e(B
+\e$BE,MQ$9$k$?$a$N!"FCDj$N%"%I%l%9$K9gCW$9$k@55,I=8=$G$9!#$=$7$F\e(B 2\e$B$DL\$O!"<h\e(B
+\e$B$j=|$/$Y$-%"%I%l%9$K9gCW$9$k$?$a$N!":G=i$N@55,I=8=$K4p$E$$$F3HD%$5$l$k@5\e(B
+\e$B5,I=8=$G$9!#\e(B
+
+\e$B$H!"@bL@$O$d$d$3$7$$$N$G$9$,!";H$&$N$O4JC1$G$9!#\e(B
+
+\e$BNc$($P\e(B @samp{foo@@example.org} \e$B$+$i%a!<%k$r<u$1<h$C$?$N$@$1$l$I!"\e(B
+Cc \e$B$N%j%9%H$K<B$OF1$8?M$N\e(B @samp{foo@@zot.example.org} \e$B$,4^$^$l$F$$$k$H!"\e(B
+\e$B9-$$JVEz$O$=$l$iN>J}$N%"%I%l%908$F$K=P$F9T$C$F$7$^$&$G$7$g$&!#\e(B
+
+\e$B$3$l$rHr$1$k$K$O!"0J2<$N$h$&$J$3$H$r$9$l$PNI$$$N$G$9\e(B:
+
+@lisp
+(setq message-prune-recipient-rules
+ '(("^\\([^@@]+\\)@@\\(.*\\)" "\\1@@.*[.]\\2")))
+@end lisp
+
+\e$BNc$($P$b$7!"\e(B@samp{cvs@@example.org} \e$B$+$i$N%a%C%;!<%8$KBP$9$k$9$Y$F$N9-$$\e(B
+\e$BJVEz$,$=$N%"%I%l%9$@$1$K9T$-!"B>$K$O9T$+$J$$$h$&$K$7$?$$\e(B (\e$B$D$^$j<u<h?M$N\e(B
+\e$B%j%9%H$K\e(B @samp{cvs@@example.org} \e$B$,$"$C$?$i!"B>$N$9$Y$F$N<u<h?M$r08@h$+\e(B
+\e$B$i=|30$7$?$$\e(B) \e$B$N$G$"$l$P\e(B:
+
+@lisp
+(setq message-prune-recipient-rules
+ '(("cvs@@example.org" ".")))
+@end lisp
+