Unable to sort columns under Dynamic Recipients in publication

Hi,

Under Publication > Properties > Dynamic Recipients, there are 3 columns namely Col 1, First Name and Email Addresses.

There is a arrow mark near to column as ^ v for ascending or descending order. When clicked on it nothing works, also i tried to use Find button, it is also not working. Below is the snapshot for it:

dynamic-recipients.jpg

Please suggest if any of you faced the similar problem and a possible solution to fix this.

Thanks,

Venkat