diff --git a/t/dotparams.od b/t/dotparams.od
new file mode 100644
index 0000000..ab00bf4
--- /dev/null
+++ b/t/dotparams.od
@@ -0,0 +1,2 @@
+# call this as ". ./dotparams.od a b" from shelltest.od
+[ "$1" = a ] && [ "$2" = b ] && [ "$#" = 2 ] || fail 115
diff --git a/t/shelltest.od b/t/shelltest.od
index c97fa62..c3ac682 100644
--- a/t/shelltest.od
+++ b/t/shelltest.od
@@ -289,4 +289,10 @@ lt
 false
 . ./nothing.od || warn 114
 
+# this one seems to be a bug in some versions of dash: the parameters to the
+# '.' command must not be ignored.
+set x y z
+. ./dotparams.od a b || fail 115
+[ "$1-$2-$3" = "x-y-z" ] || fail 116
+
 exit $FAIL