PHP string comparison hole found on configuring only number on captcha admin configuration page

Hi,
I have found a problem, while configuring the captcha as number only with image captcha module. As I have chosen the number only [0123456789], the response accepting "." after the response.
For example if the CAPTCHA code is coming with "1567898", field is accepting "1567898." or "1567898.0" [as they are numbers] .
This is the first case. Second test case :
If the CAPTCHA CODE is "0125896", it is accepting "125896".
I have found the validate function working for this checking is "captcha_validate_ignore_spaces" on captcha/captcha.module. For immediate fix I modified the file with "===" operator instead of "==" comparison operator for this particular function.

/**
 * CAPTCHA validation function to tests equality while ignoring spaces.
 * @param $solution the solution of the test.
 * @param $response the response to the test.
 * @return TRUE when equal (ignoring spaces), FALSE otherwise.
 */
function captcha_validate_ignore_spaces($solution, $response) {
  // return preg_replace('/\s/', '', $solution) == preg_replace('/\s/', '', $response);
  return preg_replace('/\s/', '', $solution) === preg_replace('/\s/', '', $response); 	
}