What is the name of the primary key column? ArcGIS tends to assume that columns
named "objectid" are available for reassignment.
You don't say how you're going about the transition, or what language/interface you're
using, but one way to preserve your data is to recreate the table schema with an initial
objectid column and renaming the primary key into something obvious ("origid"), then
copying the contents, through a view or other query to include a row number in the
objectid spot, and renaming the original PK to the new name.
- V