Domain list width

In my schema file some of the features have properties of type combo box where the list item values may be up to 35 characters long. The drop down field in the Place feature dialog window is too wide so I have to drag the scroll bar in the bottom of the Place feature dialog window to the left to see the drop down arrow. I have tried to turn of Calculate List Width in the Combo Box Property page, and also to set the List Width to 20, but this does not have an effect. The drop down feald is still to wide. How can I make the drop down field smaller? I use Bentley Map V8i SS4.