Honey-glazed gammon (ham) - What to serve with it?
In Ireland boiled or glazed ham is a staple.  Traditionally it's had with cut up cabbage (ideally you would cook the cabbage in the same water the ham was boiled in as this gives it lovely flavour) but you could just cut it up and pan fry it with a little butter.  Normally it would be served with boiled floury potatoes.  Traditionally (in Ireland) you wouldn't have a sauce with it but a parsely sauce (as stated in the other reply would be lovely) or simply serve with some strong mustard or a brown sharp sauce such as HP.  

You could also shred the ham and serve it with noodles in a hot broth with some shredded cabbage and other vegetables.

The ham is going to be centre of attention - salty, rich with a sweetness.  The cabbage and potato are happy bedfellows as the cabbage cuts through the saltyness/sweetness.  You don't want strong flavours competing with the ham and neither cabbage or potato will.