I've failed the Turing Test

Finally, I can see the end of my M.Sc in computer science. Almost all exams are over, and only the final project is to be completed. My projects advances kinda slow lately, but I hope things would get better. The topic of my project is spam (as in email-spam) and mechanisms to fight it. It is partially research, and partially technical. In order to test different web-mail vendors' spam filtering mechanisms, I've created free accounts at GMail, Yahoo! and Hotmail. Each of these vendors use the CAPTCHA anti-bot mechanism, so their services cannot be easily exploited. I've seen many of these CAPTCHA images before, and answered them correctly without a problem. And then came Yahoo!. According to them, I'm probably not human, as I failed the Turing Test three times, before I eventually managed to guess what's in the image, and pass the registration process. They had, by far, the worst looking CAPTCHA images.
I have a test of my own for computer software. My test tells if some software is usable or not. I call it "My Mom's Test". The test is quite simple: my mom is trying to use some software, with less than 1 minute training (zero is better). If she succeeds - the software is usable for everybody. If she doesn't - that's trash, and I remove it from her PC. Skype, for example, passed that test. The same test applies for web sites. Some sites are easy for her to use, while other sites frustrates her. For example, Google's search page is easy. Yahoo!'s registration process would fail "My Mom's Test" over and over again, as she would call me a hundred times before we can together "break" it's anti-bot and anti-human defense mechanisms. Therefor, it's unusable for my mom, and probably many other normal people. Too bad for them, as the profit from free services (such as web mail) comes from advertisement, which would bring more money if my mom would use it (she clicks ads).