Display Format column showing contentid instead of title

In our implementation, we are relating one content item (Xxxxx) to another (Xxxxx_category) by using an XML lookup application. The Xxxxx content type has a field (category) populated by a drop down of public Xxxxx_category’s. The Xxxxx_category’s title shows up in the drop down menu, but the value we store is the contentid. This works great. When you view a Xxxxx item’s content, the category’s title shows up instead of the contentid, like it should.

We would like to have a display format which includes a ‘category’ column, which behaves the same way. However, all we can manage to get is the contentid of the category showing up in the column. Is there a way to fix this so the title shows up in the column?

Thanks in advance,
Chris