diff --git a/testsuite/expect/globals b/testsuite/expect/globals
index 28f596526450a4f77a3f034dfd7cfcf9e772dc8c..0400690d9d6cdd6d66e228c329fa11215e0940f6 100755
--- a/testsuite/expect/globals
+++ b/testsuite/expect/globals
@@ -210,7 +210,7 @@ cset max_stress_tasks 4
 #
 # The error message that the "sleep" command prints when we run "sleep aaa".
 #
-cset sleep_error_message "(invalid time interval)|(bad character in argument)"
+cset sleep_error_message "(invalid time interval)|(bad character in argument)|(usage: sleep seconds)"
 
 # Other common variables
 set alpha                "\[a-zA-Z\]+"
diff --git a/testsuite/expect/test28.2 b/testsuite/expect/test28.2
index 062f9f5f98e251937d136ffac8b51ea2fb572ec6..e8d89d7da2aa16c2cdd88361024c4ba4efa7e3f3 100755
--- a/testsuite/expect/test28.2
+++ b/testsuite/expect/test28.2
@@ -181,7 +181,7 @@ for {set index 0} {$index < $array_end} {incr index} {
 	set err_match 0
 	spawn $bin_cat test$test_id-$job_id\_$index\.error
 	expect {
-		-re "invalid time" {
+		-re "$sleep_error_message" {
 			send_user "\nDo not worry this error is expected\n"
 			incr err_match
 		}