Sunday Yahoo! Question

Just for fun on a Sunday—I'll send a copy of Yahoo! Hacks to the first person who sends me the correct answer to the following question.
In what month/year did Yahoo! publicly launch their Search Web Services?
Be sure to include your name, mailing address, and site URL (if you have one)—and you'll need to be ok with me publishing your name/URL on this site. Employees of Onfocus Holdings, Ltd. are not eligible, this is for entertainment purposes only, void where prohibited.

Update: oops, I didn't realize this question would be so confusing. Here's a hint: try searching for the phrase yahoo search web services launch at Yahoo! Search, and check out the date on any of the announcements from Yahoo! sources in the results.