Why doesn't this replacement structured pattern work?

Why doesn't this find/replace structured pattern work?

I am trying to match this code:

        public bool SetPandGValue( byte[] pValue, byte[] gValue )
        {
            try
            {
                ic.CreateDHDestinationServiceProvider( pValue, gValue );
                return true;
            }
            catch( Exception ex )
            {
                string temp = ex.ToString();
                return false;
            }
        }

My pattern is (the xml from the resharper.user file):

    <Pattern Severity="HINT">
      <Comment>There is no need to call ToString, moron.</Comment>
      <ReplaceComment>Remove the unnecessary temp string.</ReplaceComment>
      <ReplacePattern><![CDATA[try { $trystatements$ }
catch (Exception $ex$)
{ 
     $remainingcatchstatements$
}]]></ReplacePattern>
      <SearchPattern><![CDATA[try { $trystatements$ }
catch (Exception $ex$)
{ 
    string $tmpvar$ = $ex$.ToString();
     $remainingcatchstatements$
}]]></SearchPattern>
      <Params />
      <Placeholders>
        <StatementPlaceholder Name="trystatements" Minimal="-1" Maximal="-1" />
        <StatementPlaceholder Name="remainingcatchstatements" Minimal="1" Maximal="-1" />
        <IdentifierPlaceholder Name="tmpvar" Type="" ExactType="False" RegEx="" CaseSensitive="True" />
        <IdentifierPlaceholder Name="ex" Type="" ExactType="False" RegEx="" CaseSensitive="True" />
      </Placeholders>
    </Pattern>

It does match, but when I invoke the replace there is no change.  The result I expected was this (note the ex.ToString() line is removed):

        public bool SetPandGValue( byte[] pValue, byte[] gValue )
        {
            try
            {
                ic.CreateDHDestinationServiceProvider( pValue, gValue );
                return true;
            }
            catch( Exception ex )
            {
                return false;
            }
        }

Thanks,
Josh