PSINet Inc wants it to be known that it has exceeded the stock valuation threshold it promised to IXC Communications as part its deal struck in February 1998. Under the terms of the agreement, IXC got a 20% stake in the ISP in exchange for rights of use on 10,000 miles of OC-48 (2.488 Gbps) of fiber. PSINet guaranteed IXC that its 20% would be worth at least $240m the earlier of one year after the delivery of the bandwidth was complete or four years from closing. It achieved that goal at the end of trading on Wednesday, which it says marked a 52-week session during which the stock as increased 371%. So far PSINet has activated 6,000 miles of IXC OC-12 capacity and plans to activate about 1,500 additional miles b the end of the second quarter.