Witherspoon (l) plays a ghost who haunts her former apartment

According to a poll carried out by the film's distributor Dreamworks, 77% of its weekend audience was female - an unusually high turnout.

The film sold tickets worth $16.5m (�9.2m) between Friday and Sunday, according to studio estimates.

Last week's number one, horror film The Exorcism of Emily Rose, dropped to two.

Lord of War, a drama starring Nicolas Cage as an international arms dealer, opened in third place.

Overall box office takings were up 13% on this time last year, continuing an upward trend in ticket sales after a dismal summer.

"The fall season is starting in a terrific fashion," said Paul Dergarabedian, president of box office tracking company Exhibitor Relations.

Expectations

In Just Like Heaven, Witherspoon plays a ghost who falls for the new inhabitant of her former apartment, played by Mark Ruffalo.

According to Jim Tharp, Dreamworks' head of distribution, female over-25s made up more than two thirds of its audience.

NORTH AMERICAN BOX OFFICE 1. Just Like Heaven - $16.5m (�9.2m) 2. The Exorcism of Emily Rose - $15.3m (�8.5m) 3. Lord of War - $9.2m (�5.1m) 4. The 40-Year-Old Virgin - $5.8m (�3.2m) 5. Cry Wolf - $4.6m (�2.5m) Source: Exhibitor Relations

Despite this, the film did not live up to the studio's expectations.

"We needed more romantic-minded males to show up this weekend," said Mr Tharp.

Comedy The 40-Year-Old Virgin continued to perform well at four, while horror film Cry Wolf opened at five.

Nature documentary March of the Penguins moved up a place to nine in its 13th week on release, taking its US tally to more than $70m (�38.9m).

Musical

Playing in five and eight cinemas respectively, Tim Burton's animated musical Corpse Bride and Gwyneth Paltrow's drama Proof performed strongly ahead of their nationwide releases on Friday.

Despite the recent upswing, total box office revenue for 2005 remains down by around 6% on the previous year.

Charlie and the Chocolate Factory remained the number one film worldwide after its $11.5m (�6.4m) weekend takings took its cumulative total to $175m (�97.2m).

In Australia, the Wallace and Gromit film Curse of the Were-Rabbit opened impressively with estimated first weekend takings of $1.8m (�1m).