Hi Teak,
In a word - no, you can't bounce back messages using OE. In actual fact, you don't want to initiate any response from OE because it would just confirm your email address as active to the spammers.
Just carry on deleting what you don't want. You could download a spam filtering tool such as Mailwasher to sort out your mail for you - but you'd still get the messages and you'd have to monitor for any genuine messages getting filtered.
There are ways to minimise spam, such as not giving your main email address to anywhere on line. You could use disposable email addresses. Check out these sites:
http://www.spamgourmet.com/http://email.about.com/cs/dispaddrrevs/tp/disposable.htmQUOTE:
Yahoo! Mail Disposable Email Address Service
Yahoo! Mail is a comfortable, reliable and secure email service with a reasonable amount of storage. A pretty good spam filter (including disposable email addresses) keeps the junk out.
Sneakemail Disposable Email Address Service
Sneakemail is a nice and useful disposable email address service.
Spamgourmet Disposable Email Address Service
Before you choke on all that spam, try the feature-rich and flexible disposable email addresses from Spamgourmet for protection.
Dave