After the Bell -- CommScope Slides  NEW YORK (Reuters) - Shares of communications cable maker  CommScope Inc &lt;A HREF="http://www.investor.reuters.com/FullQuote.aspx?ticker=CTV.N target=/stocks/quickinfo/fullquote"&gt;CTV.N&lt;/A&gt; fell 22 percent in after-hours trade on  Monday after it warned on its sales outlook for the fourth  quarter.