Ok, I think I've got this figured out.  I will record the 1/3 payroll (for pay period 12/22-12/28) and record 3 days of the 1/10 payroll (for the 3 Dec days of pay period 12/29-01/04).  In my best judgement I'll divide the total 1/10 payroll by 5 workdays and then multiply it by the 2 workdays that fell within that pay period.

As of 12/31
Dr: Wage Expense

Cr: Payroll liabilities account

Then reverse that entry 1/3.  Does that sound right?