I have this problem as well. The flagstones that most of the Sydney CBD is paved with are pretty slippery and not to friendly to those of us with nailed leather heels. I made a tit of myself when I slipped on my ass outside Wollies a few days ago, then there was the time I tried to walk back from the Dymocks building in teh rain in a pair of loafers. I slid about 3 metres before smacking into a pole.
Sometimes I think they made the footpaths in the Melbourne legal precinct out of those slippery stones so that when damp they would thin out the herd.
Went ass-over-teakettle in an unexpected summer storm earlier this year when caught without umbrella or rubber-soled shoes and put my foot down on a particularly greasy spot while hurrying to get under cover. Somehow didn't ruin the suit although I did have to dry clean it!