diff --git a/bin/sh/tests/parameters/mail1.0 b/bin/sh/tests/parameters/mail1.0
index 09102d811513..42e712e31ac9 100644
--- a/bin/sh/tests/parameters/mail1.0
+++ b/bin/sh/tests/parameters/mail1.0
@@ -1,14 +1,14 @@
 # Test that a non-interactive shell does not access $MAIL.
 
 goodfile=/var/empty/sh-test-goodfile
 mailfile=/var/empty/sh-test-mailfile
 T=$(mktemp sh-test.XXXXXX) || exit
-MAIL=$mailfile ktrace -i -f "$T" ${SH} -c "[ -s $goodfile ]" 2>/dev/null
+MAIL=$mailfile ktrace -t n -i -f "$T" ${SH} -c "[ -s $goodfile ]" 3>/dev/null
 if ! grep -q $goodfile "$T"; then
 	# ktrace problem
 	rc=0
 elif ! grep -q $mailfile "$T"; then
 	rc=0
 fi
 rm "$T"
 exit ${rc:-3}
diff --git a/bin/sh/tests/parameters/mail2.0 b/bin/sh/tests/parameters/mail2.0
index d594c4a74356..b1f48e0b29db 100644
--- a/bin/sh/tests/parameters/mail2.0
+++ b/bin/sh/tests/parameters/mail2.0
@@ -1,14 +1,14 @@
 # Test that an interactive shell accesses $MAIL.
 
 goodfile=/var/empty/sh-test-goodfile
 mailfile=/var/empty/sh-test-mailfile
 T=$(mktemp sh-test.XXXXXX) || exit
-ENV=$goodfile MAIL=$mailfile ktrace -i -f "$T" ${SH} +m -i </dev/null >/dev/null 2>&1
+ENV=$goodfile MAIL=$mailfile ktrace -t n -i -f "$T" ${SH} +m -i </dev/null >/dev/null 2>&1
 if ! grep -q $goodfile "$T"; then
 	# ktrace problem
 	rc=0
 elif grep -q $mailfile "$T"; then
 	rc=0
 fi
 rm "$T"
 exit ${rc:-3}