[JohnnyBB]

CELEBRITY Big Brother contestants are to be set tasks by TV stars - in a bid to perk up the last ever series.

Countdown's Rachel Riley, 23, has already signed up to test housemates' maths skills.

Producers are also eyeing Location Location Location host Kirstie Allsopp, 36, who could set contestants homemaking tasks.

And chefs such as Jamie Oliver, 34, could give cooking challenges.

The stars will enter the Big Brother compound to speak to the contestants - a first for the show.

An insider said: "The plan is to surprise the celebs and do something different.

"The tasks are one of the most popular parts of the show and producers have been thinking how to spice them up."

The celebrities are due to enter the house on January 3.

Among those thought to have signed up are Boy George, 48, and Hollywood madam Heidi Fleiss, 43. MC Hammer, 47, and Pamela Anderson, 42, are also in talks.

Bosses have pledged to spend more on fewer stars to make the last series the best ever.

THE SUN