Could Yahoo's spam filter be this bad?

I was on the road yesterday, in Washington, and trying to close a story at the same time. I had my editor send messages to my Yahoo account, which goes into my (personal) Blackberry. Today I see that Yahoo stuffed all of his mail into my spam folder. Doesn’t its machine they see that I do a lot of legitimate traffic with addresses ending in Could it possibly be because my article mentions the word “spam?” and “viagra?” Could their spam filter be working on such primitive key words? (I just experimented on that, sending the same story to my Yahoo account, and it got through.)

This issue extends far beyond spam. If Yahoo wants to close the gap with Google, the company must teach its machines to analyze our written words (and other data) with ever greater sophistication and precision. Am I wrong to think that a spam filter this far out of kilter signals problems in that area?