Yahoo, Inc. (NASDAQ: YHOO) and eBay, Inc. (NASDAQ: EBAY) are partnering up this holiday season to try and keep all those nasty but legit-looking email messages out of your Yahoo! Mail inbox. Yahoo! is by far the world's most popular web-based email service and I can only imagine the effort it takes to sniff out fraudulent and phishing email messages from tens of millions of inboxes every day.

In many cases, Yahoo! Mail users will receive official-looking messages that appears to come from eBay or its online payment division, PayPal. Those who are fooled into divulging personal information like passwords and account sign-in information usually have a large headache cleaning up the identity theft mess later. But, what if those unofficial email messages never arrived in your inbox to begin with?

Last last week, the three companies (PayPal is a wholly-owned eBay subsidiary) announced that the DomainKeys e-mail authentication system would be used to block malicious email messages from the inboxes of Yahoo! Mail users. Yahoo! stated that the upgrade would occur over its global email network for the next few weeks, allowing it to verify the domain from which email messages arrive. In other words, those Russia-based fraud emails that look like real eBay communications may soon be blocked for good.

This is a great initiative between the largest email provider and one of the largest commerce sites on the entire internet, and it's perfectly timed for the holiday e-commerce season that's already underway. Now, Yahoo! needs to market this new partnership in every way possible to let customers know what it is and how it can help them. Something like this does no deserve to be just working behind the scenes.