Pattern for detecting string(char, int) constructor

I'm struggling to get a pattern right, that would be able to detect an overloaded constructor call. The pattern should mark the following construtor call as an error, but it doesn't do so.

var s2 = new System.String( '1', 1 ); // String(char c, int count);

This is how the pattern looks like:

  <Pattern Severity="ERROR" FormatAfterReplace="True" ShortenReferences="True" Language="CSHARP">
    <Comment>Constructor Test 2</Comment>
    <ReplacePattern IsNull="True" />
    <SearchPattern>$type$( arg0,  arg1 )</SearchPattern>
    <Params />
    <Placeholders>
      <ExpressionPlaceholder Name="type" ExpressionType="System.String" ExactType="False" />
      <ExpressionPlaceholder Name="arg0" ExpressionType="System.Char" ExactType="False" />
      <ExpressionPlaceholder Name="arg1" ExpressionType="System.Int32" ExactType="False" />
    </Placeholders>
  </Pattern>


Any idea what I'm doing wrong?

Thanks in advance
Peter