Here's a cut & paste from the new 2013 rules that should be posted to the AARCMCC website any time now.
"9.6.4 All tyres must be black. Foam tyres are not allowed. Foam/cap tyres are not allowed but internal foam inserts are permitted. Tyres will not be modified in any way that will affect their original dimensions, tyre beads can be trimmed to fit into bead mount areas of rims. Control tyres using an approved closed cell foam insert only may be modified by way of no more than two external vent holes of a diameter no greater than 4mm each."
This would apply to the AKA Rebar/Closed cell inserts that are being used for the Tasmanian Titles.
Cheese