I don't believe that this is possible with SQL2K. Per BOL, "A table used in a snapshot or transactional publication can have a maximum of 255 columns and a maximum row size of 8,000 bytes." This is under the article "Publishing Data and Database Objects".
Personally, I'd say if you have a table with 255 columns you need to break that table up. To preserve existing Select functionality you could create a view, but you would need to re-write any Insert/Update/Delete procs.
cl