Williams-Sonoma Lowers 4th-Qtr. Forecast  CHICAGO (Reuters) - Williams-Sonoma Inc. &lt;A HREF="http://www.investor.reuters.com/FullQuote.aspx?ticker=WSM.N target=/stocks/quickinfo/fullquote"&gt;WSM.N&lt;/A&gt; on  Thursday posted a rise in third-quarter earnings, but the  housewares retailer lowered its fourth-quarter forecast, citing  volatile sales trends and demand for furniture that is  outstripping supply.