Around line 124 on your checkout page you should see where the return URL is set:
$WA_PP_ECO_Set_params[$nextIndex] = "ReturnURL";
$WA_PP_ECO_Set_params[$nextIndex] = "".$WAGLOBAL_Root_URL ."pp_confirm.php";
This uses the global root URL that comes from your db and adds the 'pp_confirm.php' to it. Updating the value for the root URL on the live server should make this code go to the URL that is listed.
You could code the URL in here directly to see if it makes it work, to do that you would make line 125 look like this:
$WA_PP_ECO_Set_params[$nextIndex] = "http://www.jacobsfishinghole.com/pp_confirm.php";
If you do not get the proper result with this update then there is probably a setting somewhere on your server that is causing this problem. Please give this a try and let us know the result.