I remember it too... I had a ticket get escalated from our support group in about 2003 of a customer who could not get any internet access... they had XP and had been assigned a .0 IP out of a /23 we were using for a specific pop. That /23 came out of 64.0.0.0/8 so it was clearly a bit more blanket than a class based filter. They may have had some third party firewall software on their machine, I can't remember, but I know my solution was to be a bit disgusted and then exclude .255 and .0 from the pool.
John
