text: Ebbers' Lawyers  Seek Immunity  For Witnesses Lawyers for the former WorldCom Inc. chief executive have asked a judge to force the government to grant two witnesses immunity from prosecution so they will testify on his behalf at an upcoming trial. &lt;br&gt; &lt;FONT face="verdana,MS Sans Serif,arial,helvetica" size="-2" color="#666666"&gt;&lt;B&gt;-The Washington Post&lt;/b&gt;&lt;/font&gt;