with just the 500 error, it is impossible for me to tell what the problem is.
the file that generates the captcha image is at:
WAVT_CaptchaSecurityImages.php
when I access this file directly, I get a 500 server error. this does not tell me anything other than "An error occurred"
the hosts error logs should contain more information about the cause of the error.
I need this information to be able to proceed. Without more information, I have nothing to work with to identify a cause to the problem.