[AS2] Can you set the open height of a combobox? (opening off stage)

I have a combobox that is being filled dynamically. This combobox is near the top of the stage, but the number of items in it is just a little bit longer than the amount of room below the combobox. For some reason, even though there is FAR more room below this combobox, the combobox opens UP when there are too many items in it, and only down when it fits.

When it opens up there is a scrollbar on it which implies that there would be a way to set a max height for a combobox and then scroll to the item needed. I can't find this property in the helpfiles though.

I would like to fix the max height so it always has room to open down, is there a way to do this?

Thank you!