Error capturing

I have spent considerable amount of time searching this group to find answer but couldn't. 

 I have set up a command list, "HookErrors". When an error occurs, it runs HookErrors.powerpro. In this script, I know certain errors occur in certain situation and I check the value of _LastError_ and take appropriate action. For any unanticipated errors, I display the error (_lastError_) in a 'messagebox'. This only gives what error occurred. I would also like to capture script file name and line number where it occurred. I am at loss how to do that? Appreciate your help.
 

 By the way, I am still going strong with Powerpro!!

 

 Thank you,
 Peter