Newbie Cannot run login.php Error 512 Line 1095 of Smarty.class4.php

Trying out PHPRunner 4.1 (build 320) with both a simple database I created as well as the "cars" demo.
Both run fine at the demo site.
Neither will run on my own website, and they both crash immediately with the error:
PHP error happened
Error Type: 512

Error Description: %s (gee, thanks. I guess the message didn't get passed)

URL: www.thedriftwood.com/forsale/login.php?

Error File: /web/forsale/libs/Smarty.class4.php

Error line: 1095

SQL Query:
I have no idea what this means. As I mentioned, works fine on demo site, not at all on mine.
Lines 1087-1096 of Smarty.class4.php --
/**

• trigger Smarty error
  
  *
  
• @param string $error_msg
  
• @param integer $error_type
  
  */
  
  function trigger_error($error_msg, $error_type = E_USER_WARNING)
  
  {
  
  trigger_error("Smarty error: $error_msg", $error_type);
  
  }
  Either something wasn't included, or a file is missing, or permissions aren't set right, or something ... Please help me out. I know some php (I run a phpBB) but this "Smarty" stuff is totally unknown to me.
  Thanks-
  -steve