diff --git a/bin/tests/system/nsupdate/tests.sh b/bin/tests/system/nsupdate/tests.sh
index b35d79769e..d1d72e4459 100755
--- a/bin/tests/system/nsupdate/tests.sh
+++ b/bin/tests/system/nsupdate/tests.sh
@@ -1080,7 +1080,7 @@ echo_i "ensure unresolvable server name is fatal in non-interactive mode ($n)"
 $NSUPDATE <<END > nsupdate.out 2>&1 && ret=1
     server unresolvable..
 END
-grep "couldn't get address for 'unresolvable..': not found" nsupdate.out > /dev/null || ret=1
+grep "couldn't get address for 'unresolvable..':" nsupdate.out > /dev/null || ret=1
 grep "syntax error" nsupdate.out > /dev/null || ret=1
 [ $ret = 0 ] || { echo_i "failed"; status=1; }
 
@@ -1090,7 +1090,8 @@ echo_i "ensure unresolvable server name is not fatal in interactive mode ($n)"
 $NSUPDATE -i <<END > nsupdate.out 2>&1 || ret=1
     server unresolvable..
 END
-grep "couldn't get address for 'unresolvable..': not found" nsupdate.out > /dev/null || ret=1
+grep "couldn't get address for 'unresolvable..':" nsupdate.out > /dev/null || ret=1
+grep "syntax error" nsupdate.out > /dev/null && ret=1
 [ $ret = 0 ] || { echo_i "failed"; status=1; }
 
 n=`expr $n + 1`