Hiding null date values in a crosstab.

Migrateduser

<p>I have a crosstab where one of the groups contains a date. When the date is null, i want to display a space, anything I'V tried including the code below on the expression for the binding name of the field. Yet it still displays Jan 1, 0001. How can I get it to display a space instead when the value is Null?</p>
<pre>
if (["Group5"]["CP_EXPIRATION_DATE"] == null ) {
" ";
} else {
dimension["Group5"]["CP_EXPIRATION_DATE"];
}
</pre>