Using Captcha on an HTML form within WordPress

I have the following code in place but the captcha doesn’t work 🙁

what am I missing here?

<input type="text" class="user-search" id="reverse_q" name="q" placeholder="Enter Search">
		<?php if( function_exists( 'cptch_check_custom_form' ) && cptch_check_custom_form() !== true ) echo "Please complete the CAPTCHA." ?>
        <?php if( function_exists( 'cptch_display_captcha_custom' ) ) { echo "<input type='hidden' name='cntctfrm_contact_action' value='true' />"; echo cptch_display_captcha_custom(); } ?>

	<div class="searchbutton">
	 <input type="submit" value="Search" class="searchbttn">
	 </div>

http://wordpress.org/plugins/captcha/