(Editor's note: In a press release dated May 10, 2000, the former ratings of Firstar Corp. and subsidiaries were inadvertently omitted. A corrected version follows.) NEW YORK (Standard&Poor's CreditWire) May 10, 2000--Standard&Poor's today raised the ratings on Firstar Corp. and its subsidiaries and affirmed the short-term ratings of the bank subsidiaries (see list). At the same time, the outlook was revised to stable from positive. The positive outlook was assigned in May 1999 following Firstar's announcement of a merger with St. Louis, Mo.-based Mercantile Bancorporation Inc. As a more sizable Midwest financial services competitor with $73 billion in assets, Firstar has tackled the ongoing integration with Mercantile competently. While it attended to this process, revenues and