Calendar popup on BEx key date variable

I'm using Key date variable in BEx query. It prompts to enter the calendar date in design studio. If I click on possible values, it gives the blank popup to enter the date. Is there any way I can have the calendar displayed when user clicks on possible values.

I'm aware of the date field component in design studio. I would like to have calendar displayed for BEx prompt value entry.

Thanks,

Milind,