Tracing out the undelivered mail-will reward

Hi frnds,

there is a requirement to send the mail to a list of employees.

and then i have to collect the list of employee for whom the mail is not delivered and i need to send a mail (which is not a manual one) this is to be the part of the mail sending program or a separate program that should collect the un send mail ids and the list should be send to the subordinate(admin) telling that the mail send to the following list of employee was not delivered...how to perform this plz help me...

i can even explain u still brief and clear if u want...

thanking u in advance