Is there an event for switching pages on a custom Outlook
form?

I created a multiselect listbox for a custom field on a
contact form, but it doesn't display the multiple
selections if I switch to another page and back again, or
if I close the item and open it again.

I have written an Item_Open event procedure that selects
the chosen values when the item is opened, but when the
user switches to another page and back again the
selections disappear.  The values are still saved, though.

I need to run the same procedure when switching between
the pages.  Is there such an event?

According to Microsoft, the Page object supports the Click
event, but I haven't had any success with that.

Any assistance would be greatly appreciated.  Thanks!