It should be, but even if you manage to get Word to change the link text
(i.e. the thing the link will take you to, Word will probably not change the
display text because it usually only creates that at the point when you
create the field, and there are no options within the field to allow you to
set it. To fix that, you will probably have to use VBA to insert the field.
If you are doing that within a merge, it may be easier to do it if you are
using Word 2002/2003 and can use merge events.