A PAYE scheme would be needed to establish the employee’s entitlement to benefits.
For the self-employed there is a requirement to pay a flat rate contribution (Class 2). If your profits are low you can apply for exemption. The limit for 2007/08 is £4,635. If contributions have been paid for 2007/08 and it subsequently turns out that earnings are below £4,635 a claim for repayment of contributions can be made. The deadline for this claim is 31 December 2008.
On the other hand as the contributions are only £2.20 a week, it may be advisable to pay the contributions in any event in order to maintain a contributions record. The alternative voluntary Class 3 contributions are £5.60 a week higher.