Audio Commentary to the film

There is a wonderful audo commentary to this film by Jim Dale.
He relates Kenneth Williams' favourite joke, which goes something like this:

Portman & Masons is a grand shop in the Piccidily, central London. Even the shop assistants wear suits and carnations on the lapel.
An old lady walked into the shop:-

Old Lady: How much for you cabbages?
Shop Assistant: The Cabbages madam are four pounds each.
Old Lady: Four quid for a cabbage...you can stick it up your ass!
Shop Assistant: I would madam, but I have a seven pound cucumber up there
already.