in an *.ftl, how to check for a build configuration's parameter presence?

Hi,

I need to customize the build_failed.ftl for TC 8.0.1 so that in case a "report.build.steps" configuration parameter is set, a custom email is sent. Something like:

<#if buildType.getParameters().containsKey("report.build.steps")>
  ...here goes a custom email content...
</#if>

The example above is based on Yegor Yarko's suggestion given on http://youtrack.jetbrains.com/issue/TW-14296. The problem is it doesn't work :).

"buildType.getParameters()" returns a "freemarker.template.SimpleHash". The "<#if buildType.getParameters().containsKey("report.build.steps")>" gives me  "Expression buildType.getParameters().containsKey is undefined".

How  do I iterate "buildType.getParameters()" to check if it contains a hash with a key  "report.build.steps"? I'm no good at Java so please bear with me.