Yeah, I'm the author of that post and I elected not to change the link after I changed the title. I love the irony of me originally making a date math error in the title when the bug was about date math :)

Lotus 1-2-3, the cause of the bug/feature, was released in 1983 [1].

[1] http://en.wikipedia.org/wiki/Lotus_1-2-3

FTA

>Er, an earlier version of this said the software bug was 20 years old. It's 30! Thanks, Sidhekin