The personal allowance of £9,440 is given to employees over a full tax year which runs from 6 April to 5 April.
If your wife has not worked since before 6 April 2013, then she is still entitled to a the personal allowance for a full tax year but she won't get it all at once. We are just about to reach the end of month 8 of the tax year so your wife has £6,293 (£9,440 / 12 x 8) of unused personal allowance assuming she has no other earnings in the current tax year.
If you really wanted to use that in one month, you could but there would be quite a sizeable national insurance contributions liability for your wife as the employee and the company as the employer. The personal allowance is not used against national insurance contributions.
Take a look here
for PAYE tax and NIC calculators. Put the amount you want to pay in each calculator to see the results of paying £6,293 in one month on 30 November 2013. The links to the calculators are at the bottom of each page. Use a tax code of 944L, indicate monthly for the pay period, indicate no to month 1 or week 1, £6,293 gross pay, zero in the next three boxes and a pay date of 30 November 2013 in the PAYE tax calculator. Choose monthly for the pay period, £6,293 gross pay and NI letter A in the NI calculator.
You will need to post your BVI question separately as it is on completely separate topic to the initial question so I'm not allowed to answer it as part of this question I'm afraid.
I hope this helps but let me know if you have any further questions.
or month 8 where an employee has had no earnings to date.