Our client gave IBM the IP addresses to be white listed. They filled in a lengthy time consuming form that got sent through layers of IBM management till some ops team in India finally implemented the change one week later.
We started testing. It didn't work. We went back and forth for weeks. Finally we put a conference call together with all parties. Live on the phone we sent a series of SOAP requests over the wire. "Yes, we can see the requests", came the answer. We saw no response.
Finally whilst on the phone call, one of the IBM Tech's piped up.
"Did you want this traffic to go in AND out?", he asked.
"Well, HTTP traffic isn't going to be of much use if we don't get a response to our request you idiots", was the answer I wanted to give.
They pulled out the initial firewall request form. The request was to "allow traffic from our IP addresses in through the firewall to reach the client".
They took that absolutely literally, and nobody thought to question it. They also absolved themselves of any blame.
I detested IBM from that day on.