Macro parameter of type Date not showing any result

Obviously the default displayer associated to macro parameters of type Date (the Date Picker) is not compatible with the Date converter für the parameter.

When I have set the type java.util.Date in the object WikiMacroParameterClass giving the parameter-name “someDate”, I observe the following: I can fill in the field of someDate in the macro form with the Date Picker working. But after saving the form in the code of the macro the reference $wikimacro.parameters.someDate doesn't have any value. It's just null.

You can test it with the following Velocity-code in a macro, where the conversion is working with the described setting for the parameter someDate, though only with String as an intermediate type and through another binding ($wikimakro.context or $xcontext), while wikimacro.parameters.someDate is empty.

#set($valueAsDate = $datetool.toDate('yyyy/MM/dd H:m',"$!wikimacro.context.getCurrentMacroBlock().getParameter('someDate')"))
someDate after conversion: $valueAsDate
#if ("$!wikimacro.parameters.someDate" == '')
  Parameter someDate ist empty!
#else
  Parameter somedate has the value $!wikimacro.parameters.someDate
#end

Could it have to do with the issue 14894?