Button Dropdown

[digitalphotoworld]

In tablesetup I use Button Dropdown. My problem is that I'am using ListOptions Load event to add a column that shows the gender. Now the symbol for the gender is moved to the button dropdown, too.
Is it possible to exclude columns to be moved to button dropdown?

[Webmaster]

Disable the item's ShowInDropDown attribute:
$item->ShowInDropDown = FALSE;