conversion from J# to c#

Question

I am trying to convert code from J# to C# automaticly using the dotPeek tool and I get the following code. What is it param0? The code does not compile because of it.

  public XmlException(Xml this\u00240, string s)
    : base(new StringBuffer().append("XmlParseError:").append(s).ToString())
  {
    this.this\u00240 = param0;
    if (param0 == null)
      ObjectImpl.getClass((object) param0);
    this.parseString = s;
  }

The original J# code:

public XmlException( String s ) {
            super( "XmlParseError:" + s );
            this.parseString = s;
        }


class XmlException extends Exception