Pass multivalue parameter to drillthrough report

Recently I had a request to create a drillthrough report for an aging report (actually 5 reports). I had 2 choices. One to create 5 reports or two to make one with multivalue parameters (each one of the parent reports must pass different values witch were static). Of course I decided to follow the second option. In order to do that I created the desired parameter in the parent report and I set it as multivalue and as internal.

Next I set the available values, and I set the same values and as defaults

Finally on the textbox witch I wanted to trigger the drillthrough action I inserted the parameter (OrderStatus is a multivalue parameter of the drillthrough report)

The text exression of the parent parameter was