How to make sendmail support virtual domain + virtual user?

[explorer1979]

Dear all,

I want to using sendmail as the e-mail server that can do the job support virtual domain + virtual user + SMTP smart host to our ISP's SMTP server to relay the e-mail outbound (The ISP need us give the user name and SMTP password to using their SMTP server) , but not need the SMTP auth, spam, anti-virus protect etc ...

I am newbie on sendmail, so don't know how to do the job.

Any one can help me or give me some example, thank you very much.