SEC Probes WorldCom Creditor Actions &lt;p&gt;\&lt;/p&gt;&lt;p&gt; By Dane Hamilton and Justin Hyde&lt;/p&gt;&lt;p&gt; WASHINGTON/NEW YORK (Reuters) - Federal regulators have\launched an investigation into creditor actions in the WorldCom\bankruptcy, demanding thousands of documents from bondholders\related to the largest U.S. bankruptcy, according to court\documents.&lt;/p&gt;