How do I wrap the Predecessors field in MS Project ?

bump

Yes, it is possible, but you will also make the row height of all columns taller.

Believe it or not, it is as simple as this:
1. Within your plan, click in the blank box in the left corner where the column headings meet the row numbers. This will select your entire plan.
2. Hover over the little line that separates tasks 1 and 2. You will see your cursor change shape. Now hold down on your left mouse button and drag down. (make it double the height that it is right now)
3. You will notice all rows within your schedule are now taller, and all text within each column will now wrap to the next line.

Hope this helps,
J Black