Aetna Posts \$1.29 Billion in Earnings  CHICAGO (Reuters) - Aetna Inc. &lt;A HREF="http://www.investor.reuters.com/FullQuote.aspx?ticker=AET.N target=/stocks/quickinfo/fullquote"&gt;AET.N&lt;/A&gt; on Thursday posted a  steep rise in quarterly profit as the health insurer boosted  its forecast for the rest of this year and gave a 2005 profit  estimate above analysts' views, pushing shares up 5 percent.