CalendarExtender display issue when inside a CollapsiblePanel

Hi,

I've got a list which includes several collapsible panels (as per below, 1 & 2 are collapsible panels). Each panel contains header information and can be edited when expanded. The problem arises when editing a date field. I am using a calendarextender to display the Ajax calendar control. When the calendar is displayed subsequent collapsible panels (panels that follow the active editable panel) appear above the calendar.

No matter how much mucking around I do with the calendar's z-index I can't seem to bring it above the collapsible panels.

Here's a screen print of the issue:

Any ideas?

Thanks,

Kory Arsenault