diff --git a/lib/Phpfastcache/Extensions/Drivers/Couchbasev4/Driver.php b/lib/Phpfastcache/Extensions/Drivers/Couchbasev4/Driver.php
index 380a94e..acea0fe 100644
--- a/lib/Phpfastcache/Extensions/Drivers/Couchbasev4/Driver.php
+++ b/lib/Phpfastcache/Extensions/Drivers/Couchbasev4/Driver.php
@@ -86,6 +86,11 @@ protected function driverConnect(): bool
         }
 
         if ($this->getConfig()->isDoForkDetection() && extension_loaded('posix')) {
+            // https://issues.couchbase.com/browse/PCBC-984
+            if (version_compare($extVersion, '4.2.0', '=')) {
+                throw new PhpfastcacheDriverCheckException("You are using Couchbase extension $extVersion, This version has a known bug with pcntl_fork()");
+            }
+
             $this->currentParentPID = posix_getppid();
         }
 
diff --git a/tests/Couchbasev4.test.php b/tests/Couchbasev4.test.php
index 269d2f0..61cfbee 100644
--- a/tests/Couchbasev4.test.php
+++ b/tests/Couchbasev4.test.php
@@ -21,7 +21,8 @@
 
 chdir(__DIR__);
 require_once __DIR__ . '/../vendor/autoload.php';
-$testHelper = new TestHelper('Couchbasev4 driver');
+$extensionVersion = (new ReflectionExtension('couchbase'))->getVersion();
+$testHelper       = new TestHelper('Couchbasev4 driver - Extension Version ' . $extensionVersion);
 
 $configFileName = __DIR__ . '/Configs/' . ($argv[1] ?? 'github-actions') . '.php';
 if (!file_exists($configFileName)) {
@@ -33,57 +34,74 @@
 $config = (include $configFileName)
     ->setDoForkDetection(false)
     ->setUseStaticItemCaching(false);
-
-$cacheInstance = CacheManager::getInstance('Couchbasev4', $config);
-
-$cache = new Psr16Adapter($cacheInstance);
-$value = random_int(1, 254);
-
-$cache->set('forkFailTestKey', $value);
-
-$pid = pcntl_fork();
-if ($pid == -1) {
-    $testHelper->assertFail('Unable to fork');
-} else if ($pid) {
-    $testHelper->runAsyncProcess('php "'.__DIR__ . '/Scripts/monitor_fork.php" ' . $pid);
-    pcntl_wait($status);
-} else {
-    exit($cache->get('forkFailTestKey'));
-}
-
-if ($value === pcntl_wexitstatus($status)) {
-    $testHelper->assertFail('The fork was a success was meant to lockup');
-} else {
-    $testHelper->assertPass('The forked process locked up has expected');
-}
-
-$testHelper->printInfoText('Running forking success process test');
-
-$config = (include $configFileName)
-    ->setDoForkDetection(true)
-    ->setUseStaticItemCaching(false);
-
 $cacheInstance = CacheManager::getInstance('Couchbasev4', $config);
 
-$cache = new Psr16Adapter($cacheInstance);
-$value = random_int(1, 254);
-
-$cache->set('forkSuccessTestKey', $value);
-
-$pid = pcntl_fork();
-if ($pid == -1) {
-    $testHelper->assertFail('Unable to fork');
-} else if ($pid) {
-    $testHelper->runAsyncProcess('php "'.__DIR__ . '/Scripts/monitor_fork.php" ' . $pid);
-    pcntl_wait($status);
-} else {
-    exit($cache->get('forkSuccessTestKey'));
-}
-
-if ($value === pcntl_wexitstatus($status)) {
-    $testHelper->assertPass('The exit code is the one expected');
+if (version_compare($extensionVersion, '4.2.0', '<')) {
+    $cache = new Psr16Adapter($cacheInstance);
+    $value = random_int(1, 254);
+
+    $cache->set('forkFailTestKey', $value);
+
+    $pid = pcntl_fork();
+    if ($pid == -1) {
+        $testHelper->assertFail('Unable to fork');
+    } else if ($pid) {
+        $testHelper->runAsyncProcess('php "' . __DIR__ . '/Scripts/monitor_fork.php" ' . $pid);
+        pcntl_wait($status);
+    } else {
+        exit($cache->get('forkFailTestKey'));
+    }
+
+    if ($value === pcntl_wexitstatus($status)) {
+        $testHelper->assertFail('The fork was a success was meant to lockup');
+    } else {
+        $testHelper->assertPass('The forked process locked up has expected');
+    }
+
+    $testHelper->printInfoText('Running forking success process test');
+
+    $config = (include $configFileName)
+        ->setDoForkDetection(true)
+        ->setUseStaticItemCaching(false);
+
+    $cacheInstance = CacheManager::getInstance('Couchbasev4', $config);
+
+    $cache = new Psr16Adapter($cacheInstance);
+    $value = random_int(1, 254);
+
+    $cache->set('forkSuccessTestKey', $value);
+
+    $pid = pcntl_fork();
+    if ($pid == -1) {
+        $testHelper->assertFail('Unable to fork');
+    } else if ($pid) {
+        $testHelper->runAsyncProcess('php "' . __DIR__ . '/Scripts/monitor_fork.php" ' . $pid);
+        pcntl_wait($status);
+    } else {
+        exit($cache->get('forkSuccessTestKey'));
+    }
+
+    if ($value === pcntl_wexitstatus($status)) {
+        $testHelper->assertPass('The exit code is the one expected');
+    } else {
+        $testHelper->assertFail('The exit code is unexpected');
+    }
 } else {
-    $testHelper->assertFail('The exit code is unexpected');
+    try {
+        CacheManager::getInstance(
+            'Couchbasev4',
+            (include $configFileName)
+                ->setDoForkDetection(true)
+                ->setUseStaticItemCaching(false)
+        );
+
+    } catch (\Phpfastcache\Exceptions\PhpfastcacheDriverConnectException $exception) {
+        if (str_contains($exception->getMessage(), 'bug with pcntl_fork()')) {
+            $testHelper->assertPass('correctly failed fork test due to extension version check');
+        } else {
+            $testHelper->assertFail('The exit code is unexpected');
+        }
+    }
 }
 
 try {