CustomMessage tag content not being displayed in IntelliJ

Question

I'm trying to use the RegexChecker, along with a custom error message, in IntelliJ. I've defined my check similarly to this in scalastyle_config.xml:

 <check level="warning" class="org.scalastyle.file.RegexChecker" enabled="true">
  <parameters>
   <parameter name="regex">hello</parameter>
  </parameters>
  <customMessage>Code should not contain "hello"</customMessage>
 </check>

When adding "hello" to a file, I get the following message in IntelliJ:

Regular expression matched "hello"

But what I really want is for the contents of customMessage to be displayed. Is there some setting that I'm missing?