Use wfchluc.sql to change the internal name of a lookup code and update all references to the lookup code. See: Change the internal name of a workflow object.

Use the script as follows:

sqlplus <user> @wfchluc <lookup_type> <old_luc> <new_luc> 
Enter password: <password>

Replace <lookup_type> with the lookup type of the lookup code you wish to update, replace <old_luc> with the current internal name of the lookup code, and replace <new_luc> with the new internal name of the lookup code.