Recaptcha throwing error. Form not sent

In this form I use ReCaptcha http://makkumnieuws.nl/contact.php
On “Send” I get an error stating a syntax error in
dmxConnectLib\/modules\/recaptcha.php","line":9,"message":"syntax error, unexpected '\\' (T_NS_SEPARATOR), expecting identifier (T_STRING)"
Can anyone tell me what is wrong?