Ulysses contains a number of hints to help us solve this riddle. Apart from the man in the macintosh, the town clerk, the waiter in the Ormond, and Bloom himself obviously suffer from corns. But how do corns connect to kismet? Bloom very nearly gives it all away: “... be what you call yashmak or I mean kismet. Fate”.
Gifford has kismet/fate/feet, but the full solution is found in another prize titbit, in 1895, which did the rounds of the newspapers and magazines of the time:
Anecdote Competition. A Prize of 2s. 6d. is given weekly to the person sending The Best Anecdote [...] We print a selection of the remainder [i.e. the runners-up from the prevous week] [...]
Korns on Her Kismet.
A lady living in a fashionable quarter had a piece of statuary bearing the inscription 'Kismet'. The housemaid (an Irish girl), was dusting the room one day, when the mistress appeared. 'Shure, ma’am, what’s the manin' of the 'ritin' on the bottom of this? – asked the maid, referring to the inscription on the statuary. 'Kismet means "fate"', replied the mistress. Bridget was limping painfully when she was walking with her sweetheart not long afterwards, and he asked, 'What’s the matter, Bridget?' 'Faith,' was her answer: 'I have the most tirrible korns on my kismet!' – M. S. Dean, 478, Padiham-road, Burnley.
Weekly Standard (Blackburn, England) (1895) 28 September