seperatorDashArray for table row is not working

I am trying to achieve the dashed line between rows of the table panel. But i’m unable to get it as expected by using the given properties of the RowColumnDefinition. Please help me to see if i’m doing anything wrong. My code is as below

var $ = go.GraphObject.make;
    var myDiagram = $(go.Diagram,"myDiagramDiv");
            { row:1, separatorDashArray: [5,10], separatorStroke: "black" }),                
            $(go.TextBlock,"Row,Column 0,0",{row:0,column:0,margin:2,background:"lightgrey"}),
            $(go.TextBlock,"Row,Column 0,1",{row:0,column:1,margin:2,background:"lightgrey"}),
            $(go.TextBlock,"Row,Column 1,0",{row:1,column:0,margin:2,background:"lightgrey"}),
            $(go.TextBlock,"Row,Column 1,1",{row:1,column:1,margin:2,background:"lightgrey"})            

That looks like a bug to me. Thanks for reporting it. We’ll fix in this week’s release.

Try the new beta version of GoJS 1.8.16, at GoJS - Build Interactive Diagrams for the Web.

example using beta: