Just so everyone knows, SBC or swbell.net uses yahoo to host its mail so
email comes from : smtp.sbcglobal.yahoo.com which translates to
smtp-sbc-v1.mail.vip.sc5.yahoo.com and you use it to send email with. so
that you might understand how your user is sending you email.
Also is your user trying to send you an email server that is setup on
there sbc dsl connection if so, then if you are using blacklists, then
the blacklists are probably blocking the mail. They should switch to
using a smarthost on there smtp server to send mail.
