Pivot table week grouping date format

Dear friends,
Isn't there a way to format date field while grouping it into week.
It shows all in number format as for eg. 05-08-13 - 11-08-13
I want this as 05-Aug-13 - 11-Aug-13
Appreciate your help on this.

rgds,
Prad

This is not possible. All of the original formats are ignored and the grouped field is text so it may not use a date format. The only way it may be done is to create a custom grouping field in your data source that is formatted in your desired fashion.