diff --git a/historic/jam/src/build.jam b/historic/jam/src/build.jam
index df82cb79a..b4fb78ff2 100644
--- a/historic/jam/src/build.jam
+++ b/historic/jam/src/build.jam
@@ -234,7 +234,7 @@ actions .md {    mkdir $(<) }
 rule .exe
 {
     local exe = $(<) ;
-    if $(NT) { exe = $(exe:S=.exe) ; }
+    if $(NT) || ( $(UNIX) && $(OS) = CYGWIN ) { exe = $(exe:S=.exe) ; }
     LOCATE on $(exe) = $(locate-target) ;
     DEPENDS $(exe) : $(>) ;
     DEPENDS $(exe) : $(locate-target) ;
diff --git a/jam_src/build.jam b/jam_src/build.jam
index df82cb79a..b4fb78ff2 100644
--- a/jam_src/build.jam
+++ b/jam_src/build.jam
@@ -234,7 +234,7 @@ actions .md {    mkdir $(<) }
 rule .exe
 {
     local exe = $(<) ;
-    if $(NT) { exe = $(exe:S=.exe) ; }
+    if $(NT) || ( $(UNIX) && $(OS) = CYGWIN ) { exe = $(exe:S=.exe) ; }
     LOCATE on $(exe) = $(locate-target) ;
     DEPENDS $(exe) : $(>) ;
     DEPENDS $(exe) : $(locate-target) ;