Cursor runs off to other controls on the form

[yukesh]

I have a userform on which I have a comboBox, some textboxes and some optionButtons. the combobox is populated with some items. i find that if i keep the downkey on the keyboard pressed while i am reading all the items of the combobox list, after the last item the cursor goes off to the next text box, and then the next text box..rather than staying inside the combo box or inside a textbox. Is there anyway I can keep the cursor from running off to other controls, even if I keep the downkey pressed?