Can we make a post redundant (and make the appropriate redundancy payment) and then re-employ the post holder under a new contact of employment in the near future?

I am a charity trustee. We employ one person in connection with a post that was funded by a three-year grant that ended on 31 December 2007. We have continued to employ this person since then on an ad hoc basis, and on a reduced income, to work on small projects. We have told the employee that his rights to the statutory redundancy payment (as at 31 December 2007) are not affected by his willingness to continue working for the charity.

We are hoping to secure future income that may enable us to employ this person going forwards. However, this future income is uncertain. One option the trustees are considering is to make this person’s post redundant, on the basis that the work associated with the post ended on 31 December 2007, even though he has continued to work with us since then. His work in 2008 is in connection with specific activities that will end soon. I would like to know if it would be legitimate to make him redundant now, and maybe re-employ him in the coming months if we then have arrangements in place that will secure a future income stream. We are not expecting any objection from the employee. Our primary concern is with regard to the tax rules on redundancy payments.