AGEISM is certainly not a crime you'd want to pin on Peter Hall. Often at his productions, you wonder whether you're watching a play or a pension scheme. Alan Howard's Lear, for example, must have been all of five when he sired his eldest daughter, so formidably mature did she seem in the recent Hall staging. And is Felicity Kendall anybody's idea, these days, of the vivaciously careerist high-class tart Hall had her play in Feydeau's Mind Millie For Me?

You have to applaud this director's loyalty: he seems determined, for instance, to get Dulcie Gray and Michael Denison (the F R and Queenie Leavis of showbiz) into the Guinness Book of Records for length of service to an insatiable public. But such is his penchant for casting out-of-kilter, generation-wise, you feel that if we were to direct a real oldies' knees- up, Kander and Ebb's 70 Girls 70, say - it would have to be performed via a ouija board.

All of which is to say that it's very much not a first that Elaine Paige is so uncomfortably cast as Celimene in Hall's new staging of The Misanthrope. Imagine replacing John Malkovich with Barry Manilow in Dangerous Liaisons and you'll get some sense of the mismatch between Moliere's manipulative, steelily-sophisticated - and spiritually empty - coquette from the Sun King's France, and the nice, warm, down-to-earth and endlessly ordinary Ms Paige. Just about the only salon you could imagine this performer gracing is a beauty salon.

The role is vital in shaping our perception of Alceste, the title character. How can we take quite seriously his pose as the lone champion of honesty, and the snarlingly disinterested scourge of hypocrisy when he's infatuated with a woman he knows to be a walking symbol of twisted social values? Michael Pennington has the right kind of thin curdled smile and sickly superiority for Alceste, but his passion seems to stem from no lower than his throat. A satirist who cannot see that he should, logically, be one of his own butts, this anti-hero needs to be both more tragic and more ridiculous.

Part of his problem is Paige, who is bewigged and dressed up so that she resembled what you'd get if you mated Ronnie Corbett with Danny La Rue. A femme fatale she isn't; more like an outtake from Carry On Bitching. But then the cast receive little support from Ranjit Bolt's couplet translation which lacks his usual sparkle (it is to Moliere what Clive James' comic verse epics are to Pope) and which relies too heavily on the outraged delight you can still cause by sticking expressions like "shit" and "piss off" in a high-toned context.

From Tony Harrison's version, set in De Gaulle's Paris, to Martin Crimp's more recent adaptation, set amidst the media glitterati of the present day, productions of The Misanthrope have been keen to stress the timelessness and topicality of its war between the worldly and the unworldly, extremism and accommodation. There can be snags with this (in the modern world, if you attacked the equivalent of a crappy court versifier, you'd be met with acclaim rather than the threat of arrest). But you also risk over- reducing Moliere's cast to a collection of theatrical types when you set it in as bare and textureless a 17th-century milieu as Hall achieves here. At the start, an actor in a sun mask moons at us: by the end, you feel like returning the compliment.