Temporary worker - contract expiring in August

Hi. I am currently covering a maternity leave HR role. The contract is due to expire in August, The lady is very sick and will probably not be back until next year. I am not happy on salary I am on and feel it is under market rates. for eg. there is less than 2k difference between mine and REceptionist and I am her manager. I have taken a drop of over 2k from PA to office manager. I presume a new contract will need to be drawn up by agency as contract states that contract will go on no longer than 7th August. Am i entitled to bring up money situation an demand more money? I started in January and if it goes on for another year, 'temporary' contract will be 1.5 years. I have committed to this role and feel I should be compensated with a fair salary

The old saying "if you don't ask, you don't get" applies in this situation. You should however be able to backup the request with firm facts and figures about why the company should pay more money in these testing times.

Thanks, I have salary guide for 2009 and advetisements for positions similar HR Generalist etc. But can I do this even if contract was agreed back in Jan. Presume new contract would allow new salary. what do you think??They are very tight with money so it will not be easy!!!!