If you use Analytical Accounting, checkout the new GP2013 feature Copy AA Trx Dimensions for POP, SOP, GL
Feature When Pam or Jay Reveals It: Copy AA Trx Dimensions for POP, SOP, GL – Inside Microsoft Dynamics GP – Site Home – MSDN Blogs
General Ledger & FinancialsSales, Purchasing & InventoryGP 2013
Archived post from 2012. Dynamics GP and the links it points to have changed since; check current documentation before relying on version-specific steps.