I worked for their competitor. The customer was a big govt site. One side of the building was IBM, and we were on the other side. Sometimes we'd get called in late at night or on the weekends. Get to the site and the customer would try to talk us into fixing one of the IBM machines, because the IBM guys weren't 24/7 coverage. Sometimes we'd go look, and if it was something obvious we would tell the customer what to do to try to fix it, but we couldn't touch it.