NI exception for first year

[shebbar]

Hi,

I am from commonwealth country and working in UK. My first year of employemtn here and I am not paying NI. Employer told me no NI for first year. My gross per annum is 40K.
However my wife on a contract, rate 150/day. She is also within first year but the umbrella company she uses is deducting NI; they say there is no such exception.

Can someone explain what this "one year exception" is about? And, is it possible to reclaim the payments made by my wife.

thanks

[pawncob]

I've not come across it.

Do you mean this?

http://www.hmrc.gov.uk/nic/work/embassy.htm