Wall St. Seen Mixed; PeopleSoft Seen Up  LONDON (Reuters) - Wall Street stocks were expected to open  mixed on Friday, with technology stocks gaining ground led by  PeopleSoft Inc &lt;A HREF="http://www.investor.reuters.com/FullQuote.aspx?ticker=PSFT.O target=/stocks/quickinfo/fullquote"&gt;PSFT.O&lt;/A&gt; but blue chips held back by a profit  warning from Alcoa Inc. &lt;A HREF="http://www.investor.reuters.com/FullQuote.aspx?ticker=AA.N target=/stocks/quickinfo/fullquote"&gt;AA.N&lt;/A&gt;.