diff --git a/tests/UnitTests/SmartyMethodsTests/RegisterModifier/RegisterModifierFirstClassCallablesTest.php b/tests/UnitTests/SmartyMethodsTests/RegisterModifier/RegisterModifierFirstClassCallablesTest.php
index b8dd6c00..2ba2f801 100644
--- a/tests/UnitTests/SmartyMethodsTests/RegisterModifier/RegisterModifierFirstClassCallablesTest.php
+++ b/tests/UnitTests/SmartyMethodsTests/RegisterModifier/RegisterModifierFirstClassCallablesTest.php
@@ -1,156 +1,55 @@
 <?php
-/**
- * Smarty PHPunit tests register->modifier / unregister->modifier methods
- *
- * @package PHPunit
- * @author  Uwe Tews
- */
-
-/**
- * class for register->modifier / unregister->modifier methods tests
- *
- * @runTestsInSeparateProcess
- * @preserveGlobalState disabled
- * @backupStaticAttributes enabled
- */
-class RegisterModifierTest extends PHPUnit_Smarty
-{
-    public function setUp(): void
-    {
-        $this->setUpSmarty(__DIR__);
-    }
-
-
-    public function testInit()
-    {
-        $this->cleanDirs();
-    }
-    /**
-     * test register->modifier method for function
-     */
-    public function testRegisterModifier()
-    {
-        $this->smarty->registerPlugin(Smarty::PLUGIN_MODIFIER, 'testmodifier', 'mymodifier');
-        $this->assertEquals('mymodifier', $this->smarty->registered_plugins[Smarty::PLUGIN_MODIFIER]['testmodifier'][0]);
-        $this->smarty->assign('foo', 'foo');
-        $this->smarty->assign('bar', 'bar');
-        $this->assertEquals('foo function blar bar', $this->smarty->fetch('eval:{$foo|testmodifier:blar:$bar}'));
-    }
-
-    /**
-     * test register->modifier method for classes
-     */
-    public function testRegisterModifierClass()
-    {
-        $this->smarty->registerPlugin(Smarty::PLUGIN_MODIFIER, 'testmodifier', array('mymodifierclass', 'static_method'));
-        $this->smarty->assign('foo', 'foo');
-        $this->smarty->assign('bar', 'bar');
-        $this->assertEquals('foo static blar bar', $this->smarty->fetch('eval:{$foo|testmodifier:blar:$bar}'));
-    }
-
-    /**
-     * test register->modifier method for objects
-     */
-    public function testRegisterModifierObject()
-    {
-        $obj = new mymodifierclass;
-        $this->smarty->registerPlugin(Smarty::PLUGIN_MODIFIER, 'testmodifier', array($obj, 'object_method'));
-        $this->smarty->assign('foo', 'foo');
-        $this->smarty->assign('bar', 'bar');
-        $this->assertEquals('foo object blar bar', $this->smarty->fetch('eval:{$foo|testmodifier:blar:$bar}'));
-    }
-
-    /**
-     * test unregister->modifier method
-     */
-    public function testUnregisterModifier()
-    {
-        $this->smarty->registerPlugin(Smarty::PLUGIN_MODIFIER, 'testmodifier', 'mymodifier');
-        $this->smarty->unregisterPlugin(Smarty::PLUGIN_MODIFIER, 'testmodifier');
-        $this->assertFalse(isset($this->smarty->registered_plugins[Smarty::PLUGIN_MODIFIER]['testmodifier']));
-    }
-
-    /**
-     * test unregister->modifier method not registered
-     */
-    public function testUnregisterModifierNotRegistered()
-    {
-        $this->smarty->unregisterPlugin(Smarty::PLUGIN_MODIFIER, 'testmodifier');
-        $this->assertFalse(isset($this->smarty->registered_plugins[Smarty::PLUGIN_MODIFIER]['testmodifier']));
-    }
-
-    /**
-     * test unregister->modifier method other registered
-     */
-    public function testUnregisterModifierOtherRegistered()
-    {
-        $this->smarty->registerPlugin(Smarty::PLUGIN_BLOCK, 'testmodifier', 'mymodifier');
-        $this->smarty->unregisterPlugin(Smarty::PLUGIN_MODIFIER, 'testmodifier');
-        $this->assertTrue(isset($this->smarty->registered_plugins[Smarty::PLUGIN_BLOCK]['testmodifier']));
-    }
-
-	public function testRegisterFirstClassCallable() {
-		// skip test if PHP version is lower than 8.1
-		if (PHP_VERSION_ID < 81000) {
-			$this->markTestSkipped('PHP 8.1 or later is required');
-		}
-
-		$this->smarty->registerPlugin(Smarty::PLUGIN_MODIFIER, 'testmodifier', strrev(...));
-		$this->assertEquals('mosredna', $this->smarty->fetch('string:{"andersom"|testmodifier}'));
-	}
-
-	public function testRegisterFirstClassCallableSameName() {
-
-		// skip test if PHP version is lower than 8.1
-		if (PHP_VERSION_ID < 81000) {
-			$this->markTestSkipped('PHP 8.1 or later is required');
-		}
-
-		$this->smarty->registerPlugin(Smarty::PLUGIN_MODIFIER, 'mymodifier', mymodifier(...));
-		$this->assertEquals('mosredna', $this->smarty->fetch('string:{"andersom"|mymodifier:"":""}'));
-	}
-	public function testRegisterFirstClassCallableAsFunc() {
-		// skip test if PHP version is lower than 8.1
-		if (PHP_VERSION_ID < 81000) {
-			$this->markTestSkipped('PHP 8.1 or later is required');
-		}
-
-		$this->smarty->registerPlugin(Smarty::PLUGIN_MODIFIER, 'kprint_r_out', strrev(...));
-		$this->smarty->assign('myVar', 'andersom');
-		$this->assertEquals('mosredna', $this->smarty->fetch('string:{kprint_r_out($myVar)}'));
-	}
+// first class callables where introduced in PHP 8.1
+if (PHP_VERSION_ID >= 80100) {
 
 	/**
-	 * @return void
-	 * @throws SmartyException
-	 * @group RegisterFirstClassCallableSameNameAsPhpFunc
+	 * class for register modifier with (first class) callables tests
+	 *
+	 * @runTestsInSeparateProcess
+	 * @preserveGlobalState disabled
+	 * @backupStaticAttributes enabled
 	 */
-	public function testRegisterFirstClassCallableSameNameAsPhpFunc() {
-		// skip test if PHP version is lower than 8.1
-		if (PHP_VERSION_ID < 81000) {
-			$this->markTestSkipped('PHP 8.1 or later is required');
+	class RegisterModifierFirstClassCallablesTest extends PHPUnit_Smarty
+	{
+		public function setUp(): void
+		{
+			$this->setUpSmarty(__DIR__);
+		}
+
+
+		public function testInit()
+		{
+			$this->cleanDirs();
+		}
+
+		public function testRegisterFirstClassCallable()
+		{
+			$this->smarty->registerPlugin(Smarty::PLUGIN_MODIFIER, 'testmodifier', eval('return strrev(...);'));
+			$this->assertEquals('mosredna', $this->smarty->fetch('string:{"andersom"|testmodifier}'));
+		}
+
+		public function testRegisterFirstClassCallableSameName()
+		{
+			$this->smarty->registerPlugin(Smarty::PLUGIN_MODIFIER, 'mymodifier', eval('return strrev(...);'));
+			$this->assertEquals('mosredna', $this->smarty->fetch('string:{"andersom"|mymodifier}'));
+		}
+
+		public function testRegisterFirstClassCallableAsFunc()
+		{
+			$this->smarty->registerPlugin(Smarty::PLUGIN_MODIFIER, 'kprint_r_out', eval('return strrev(...);'));
+			$this->smarty->assign('myVar', 'andersom');
+			$this->assertEquals('mosredna', $this->smarty->fetch('string:{kprint_r_out($myVar)}'));
+		}
+
+		public function testRegisterFirstClassCallableSameNameAsPhpFunc()
+		{
+			$this->smarty->registerPlugin(Smarty::PLUGIN_MODIFIER, 'mymodifierfcc', eval('return strrev(...);'));
+			$this->assertEquals('mosredna', $this->smarty->fetch('string:{mymodifierfcc("andersom")}'));
 		}
 
-		$this->smarty->registerPlugin(Smarty::PLUGIN_MODIFIER, 'mymodifier', strrev(...));
-		$this->assertEquals('mosredna', $this->smarty->fetch('string:{mymodifier("andersom","","")}'));
 	}
-
 }
-
-function mymodifier($a, $b, $c)
+function mymodifierfcc($a, $b, $c)
 {
     return "$a function $b $c";
 }
-
-class mymodifierclass
-{
-    static function static_method($a, $b, $c)
-    {
-        return "$a static $b $c";
-    }
-
-    public function object_method($a, $b, $c)
-    {
-        return "$a object $b $c";
-    }
-}