If the employee is weekly paid, then yes absolutely. The P45 is still current for this tax year for week 52 (2010/11) so treat it the same as at any other time in the year.
If they're monthly paid and have already had month 12 paid then don't apply it to this tax year. When you come to processing the first period of next year (2011/12) you may still apply the tax code shown but don't enter the previous pay and tax or wk1/m1.