diff --git a/.travis.yml b/.travis.yml
index 230e422..fdaeda9 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -24,6 +24,8 @@ before_install:
 - sudo add-apt-repository ppa:pinepain/libv8-${V8} -y
 - sudo apt-get update -q
 - sudo apt-get install -y libv8-${V8}-dev
+ - php -i
+ - php-config || true
 
 before_script:
 - echo 'variables_order = "EGPCS"'>> ~/.phpenv/versions/$(phpenv version-name)/etc/php.ini
diff --git a/tests/V8Int32Value.phpt b/tests/V8Int32Value.phpt
index abeb074..d2be188 100644
--- a/tests/V8Int32Value.phpt
+++ b/tests/V8Int32Value.phpt
@@ -54,7 +54,7 @@ $helper->space();
 
 
 $helper->header('Test negative value in constructor');
-$value = new V8\Int32Value($isolate, -123.456);
+$value = new V8\Int32Value($isolate, -123);
 $helper->method_export($value, 'Value');
 $helper->method_export($value, 'BooleanValue', [$context]);
 $helper->method_export($value, 'NumberValue', [$context]);
diff --git a/tests/V8IntegerValue.phpt b/tests/V8IntegerValue.phpt
index 48dfe5b..29964c2 100644
--- a/tests/V8IntegerValue.phpt
+++ b/tests/V8IntegerValue.phpt
@@ -54,7 +54,7 @@ $helper->space();
 
 
 $helper->header('Test negative value in constructor');
-$value = new V8\IntegerValue($isolate, -123.456);
+$value = new V8\IntegerValue($isolate, -123);
 $helper->method_export($value, 'Value');
 $helper->method_export($value, 'BooleanValue', [$context]);
 $helper->method_export($value, 'NumberValue', [$context]);
diff --git a/tests/V8StringValue.phpt b/tests/V8StringValue.phpt
index 93db112..0e44a52 100644
--- a/tests/V8StringValue.phpt
+++ b/tests/V8StringValue.phpt
@@ -13,7 +13,6 @@ $v8_helper = new PhpV8Helpers($helper);
 
 // Tests:
 
-
 $isolate = new V8\Isolate();
 
 $default = new V8\StringValue($isolate);
@@ -87,7 +86,6 @@ foreach (['Hello, world!', 'Привет, мир!', 'こんにちは世界'] as
 $helper->method_export($value, 'ContainsOnlyOneByte');
 
 $helper->function_export('strlen', [$value->Value()]);
- $helper->function_export('mb_strlen', [$value->Value()]);
 $helper->space();
 }
 
@@ -207,7 +205,6 @@ V8\StringValue->Utf8Length(): int(13)
 V8\StringValue->IsOneByte(): bool(true)
 V8\StringValue->ContainsOnlyOneByte(): bool(true)
 strlen(): 13
-mb_strlen(): 13
 
 
 V8\StringValue->Value(): string(21) "Привет, мир!"
@@ -216,7 +213,6 @@ V8\StringValue->Utf8Length(): int(21)
 V8\StringValue->IsOneByte(): bool(false)
 V8\StringValue->ContainsOnlyOneByte(): bool(false)
 strlen(): 21
-mb_strlen(): 12
 
 
 V8\StringValue->Value(): string(21) "こんにちは世界"
@@ -225,4 +221,3 @@ V8\StringValue->Utf8Length(): int(21)
 V8\StringValue->IsOneByte(): bool(false)
 V8\StringValue->ContainsOnlyOneByte(): bool(false)
 strlen(): 21
-mb_strlen(): 7
</div><div class="naked_ctrl">
<form action="/index.cgi/contrast" method="get" name="gate">
<p><a href="http://altstyle.alfasado.net">AltStyle</a> によって変換されたページ <a href="https://patch-diff.githubusercontent.com/raw/phpv8/php-v8/pull/17.diff">(-&gt;オリジナル)</a>
/ <label>アドレス: <input type="text" name="naked_post_url" value="https://patch-diff.githubusercontent.com/raw/phpv8/php-v8/pull/17.diff" size="22" /></label> <label>モード: <select name="naked_post_mode">
<option value="default">デフォルト</option>
<option value="speech">音声ブラウザ</option>
<option value="ruby">ルビ付き</option>
<option value="contrast" selected="selected">配色反転</option>
<option value="larger-text">文字拡大</option>
<option value="mobile">モバイル</option>
</select>
<input type="submit" value="表示" />
</p>
</form>
</div>