diff --git a/src/Socialbox/Classes/StandardMethods/Verification/VerificationAnswerImageCaptcha.php b/src/Socialbox/Classes/StandardMethods/Verification/VerificationAnswerImageCaptcha.php
index c6a835b..1d3d9a7 100644
--- a/src/Socialbox/Classes/StandardMethods/Verification/VerificationAnswerImageCaptcha.php
+++ b/src/Socialbox/Classes/StandardMethods/Verification/VerificationAnswerImageCaptcha.php
@@ -42,7 +42,7 @@
 
             try
             {
-                $result = CaptchaManager::answerCaptcha($session->getPeerUuid(), $rpcRequest->getParameter('answer'));
+                $result = CaptchaManager::answerCaptcha($session->getPeerUuid(), (string)$rpcRequest->getParameter('answer'));
 
                 if($result)
                 {