Filter a datasource where key = #

Hi all,

I need to filter a datasource on a specific dimension. This dimension has 4 different key values, where one of the key values is #

The filter is set via a Dropdown Box. The problem is that the # sign seems to be a wildcard etc. When I execute the following script, the data source shows all of the different key values.

DS.setFilter("DIM X", "#");

Any ideas how I can solve this?

Thanks!