zOrdering question

zOrdering question

I probably missed something obvious in the documentation, but I can't
seem to solve the following:
I have a form which uses DatePicker to select a date. This form works
perfectly, including the date picker.
However, when I put the form in a Dialog, the DatePicker always ends
up behind the Dialog, no matter what values I use for the zIndex
option on the DatePicker and the Dialog.
Has anyone got clues, or examples of situations where this does work
correctly? Thanks already!
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