Gross-ups not working for Alaska employees in 2012 with Vertex 297

Our Gross-ups for Alaska based employees (Tax area 02) have stopped working in 2012 (workd in 2011) for any pay type.  We are on Vertex 297.  We have all the tax rates defined for 2012 but the interim workbench cannot calculate the desired net amount.  The gross-ups work fine for any employee outside Alaska and they worked fine for Alaska employees in 2011 - set-up is same and I have verified the 2012 UI rates in set-up.  We suspect that the tax type G is causing the issue because when I override the G tax amount, the gross works like