I purchased a new Honeywell RTH8500 thermostat in the summer, and did the installation myself, but am now having trouble with the heat not coming on (AC was working fine in the summertime). I think there is a problem with the wiring, as I tried hooking back up my old thermostat and the heat came out just fine.

In my old thermostat, there were G, O, B, Y, W, C and R terminals, with the following wiring setup:
Green wire -> G terminal
White wire -> B terminal
Black wire -> Y terminal
Red wire -> R terminal
In addition, there was a jumper cable between the Y and W terminals.
There is also a brown wire, but it was never connected to any terminal, and both heating and AC worked fine.

Here's a link to the old thermostat configuration (yes, I know the red cable is not connected in the pic)
http://img257.imageshack.us/img257/4338/simplecomfort2001thermo.jpg

Now on the new thermostat, there are the following terminals:
Rc, R, W, Y, G, C
There is a jumper wire connecting Rc to R.
I connected the existing wires as follows:
Red wire -> R terminal
White wire -> W terminal
Black wire -> Y terminal
Green wire -> G terminal

The AC still works fine, but heat does not come on at all. I'm wondering if it's because in the old setup, Y and W had a jumper cable between them, but in the new setup, there is no connection between the Y and W terminals?
Or also, do I need to connect the brown wire in any way?

Any help would be GREATLY appreciated.