diff --git a/ext/mbstring/tests/illformed_utf_sequences.phpt b/ext/mbstring/tests/illformed_utf_sequences.phpt
index b5b9d94db84..378b956d681 100644
--- a/ext/mbstring/tests/illformed_utf_sequences.phpt
+++ b/ext/mbstring/tests/illformed_utf_sequences.phpt
@@ -25,28 +25,28 @@ var_dump(chk_enc("\x31\x32\x33", 0));
 var_dump(chk_enc("\x41\x42\x43", 0));
 var_dump(chk_enc("\xc0\xb1\xc0\xb2\xc0\xb3", 6));
 var_dump(chk_enc("\xc1\x81\xc1\x82\xc1\x83", 6));
-var_dump(chk_enc("\xe0\x80\xb1\xe0\x80\xb2\xe0\x80\xb3", 6));
-var_dump(chk_enc("\xe0\x81\x81\xe0\x81\x82\xe0\x81\x83", 6));
-var_dump(chk_enc("\xf0\x80\x80\xb1\xf0\x80\x80\xb2\xf0\x80\x80\xb3", 9));
-var_dump(chk_enc("\xf0\x80\x81\x81\xf0\x80\x81\x82\xf0\x81\x83", 8));
+var_dump(chk_enc("\xe0\x80\xb1\xe0\x80\xb2\xe0\x80\xb3", 9));
+var_dump(chk_enc("\xe0\x81\x81\xe0\x81\x82\xe0\x81\x83", 9));
+var_dump(chk_enc("\xf0\x80\x80\xb1\xf0\x80\x80\xb2\xf0\x80\x80\xb3", 12));
+var_dump(chk_enc("\xf0\x80\x81\x81\xf0\x80\x81\x82\xf0\x81\x83", 11));
 var_dump(chk_enc("\xf8\x80\x80\x80\xb1\xf8\x80\x80\x80\xb2\xf8\x80\x80\x80\xb3", 15));
 var_dump(chk_enc("\xf8\x80\x80\x81\x81\xf8\x80\x80\x81\x82\xf8\x80\x80\x81\x83", 15));
 var_dump(chk_enc("\xfc\x80\x80\x80\x80\xb1\xfc\x80\x80\x80\x80\xb2\xfc\x80\x80\x80\x80\xb3", 18));
 var_dump(chk_enc("\xfc\x80\x80\x80\x81\x81\xfc\x80\x80\x80\x81\x82\xfc\x80\x80\x80\x81\x83", 18));
 
 var_dump(chk_enc("\xc2\xa2\xc2\xa3\xc2\xa5", 0));
-var_dump(chk_enc("\xe0\x82\xa2\xe0\x82\xa3\xe0\x82\xa5", 6));
-var_dump(chk_enc("\xf0\x80\x82\xa2\xf0\x80\x82\xa3\xf0\x80\x82\xa5", 9));
+var_dump(chk_enc("\xe0\x82\xa2\xe0\x82\xa3\xe0\x82\xa5", 9));
+var_dump(chk_enc("\xf0\x80\x82\xa2\xf0\x80\x82\xa3\xf0\x80\x82\xa5", 12));
 var_dump(chk_enc("\xf8\x80\x80\x82\xa2\xf8\x80\x80\x82\xa3\xf8\x80\x80\x82\xa5", 15));
 var_dump(chk_enc("\xfc\x80\x80\x80\x82\xa2\xfc\x80\x80\x80\x82\xa3\xfc\x80\x80\x80\x82\xa5", 18));
 
 var_dump(chk_enc("\xc1\xbf", 2));
 var_dump(chk_enc("\xc2\x80", 0));
 var_dump(chk_enc("\xdf\xbf", 0));
-var_dump(chk_enc("\xe0\x9f\xff", 2));
+var_dump(chk_enc("\xe0\x9f\xff", 3));
 var_dump(chk_enc("\xe0\xa0\x80", 2));
 var_dump(chk_enc("\xef\xbf\xbf", 0));
-var_dump(chk_enc("\xf0\x8f\xbf\xbf", 3));
+var_dump(chk_enc("\xf0\x8f\xbf\xbf", 4));
 var_dump(chk_enc("\xf0\x90\x80\x80", 0));
 var_dump(chk_enc("\xf7\xbf\xbf\xbf", 4));
 var_dump(chk_enc("\xf8\x87\xbf\xbf\xbf", 5));
@@ -61,7 +61,7 @@ echo "UTF-8 and surrogates area\n";
 $out = '';
 $cnt = 0;
 for ($i = 0xd7ff; $i <= 0xe000; ++$i) {
-	$s = chk_enc(pack('C3', 0xe0 | ($i >> 12), 0x80 | ($i >> 6) & 0x3f, 0x80 | $i & 0x3f), 2);
+	$s = chk_enc(pack('C3', 0xe0 | ($i >> 12), 0x80 | ($i >> 6) & 0x3f, 0x80 | $i & 0x3f), 3);
 	if ($s === false) {
 		$cnt++;
 	} else {