Make a spice bag from the peppercorns, mustard seeds and pickling spice; set aside.
In a quite large pot, combine everything from the orange zest down to and including the vinegar.
Bring to a boil, stirring constantly so you don't get any scorching, then lower to a simmer and let simmer uncovered on low for 45 minutes, stirring occasionally.
Add spice bag, allspice and curry powder. Stir in, and let simmer for another 30 minutes or until thick enough to mound up on a spoon.
Spoon into quarter-litre (½ US pint) jars.
Leave 2 cm (½ inch) headspace.
Debubble, adjust headspace.
Wipe jar rims.
Put lids on.
Process in a water bath or steam canner.
Process for 10 minutes; increase time as needed for your altitude.