Your XML is bad, as you've been told. So how about we explore alternative schemas. 
<BLOCK>
  <RECORD>
    <FIELD id="Containing a space">Value1</FIELD> 
    <FIELD id="/Containing a slash/">Value2</FIELD>
  </RECORD>
</BLOCK>

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In reply to Re: Problem in parsing XML file with spaces or slashes in a tag by ikegami
in thread Problem in parsing XML file with spaces or slashes in a tag by bgupta

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