I need a little advice.  Here's the situation:
My wife and I currently have a 3 year old male, fixed, American Shorthair,
and a 2 year old, female, fixed Shetland Sheepdog who get along perfectly
well.
Lately, we've had a number of things come up where my wife and I must leave
town for a day or two.  We used to take them both to a friend's house, but
he doesn't really like cats in general, and has requested that we only leave
him the dog from now on.

For some time now, we had been entertaining the idea of getting a second
cat, and this pushed us over the top, thinking that they could keep each
other company while we're gone on any future short trips (the current cat
hates being alone).

So last weekend, we picked up a 10 week old female kitten from a nearby
neighbor that happened to have a litter needing homes.
The dog actually seems rather excited that there's a new critter in the
house, and she and the kitten seem to be getting along fine (though I think
the sheer size fo the dog intimidates the kitten).
However, the elder cat is not nearly as accepting...  He's not acting
aggressively, and he's made no indications that he might attack or otherwise
harm the new kitten, but he hisses almost constantly whenever she is nearby,
and has lately been retreating to the dark, under-used portions of the
house, specifically the laundry room, for long periods of time.  Even worse,
if he's within site of her and I try to so much as touch him, he'll hiss at
me as well.
However, the strange thing is that occassionally, he'll seem like he wants
to play with the kitten, making a gentle swat at her and running just far
enough away that she has to bound after him in chase, but at any point in
that he will revert into his anti-social mode and start hissing again.

Granted, it's only been about 4 days, but I would think that by now he would
have calmed down at least a little bit.
We've been keeping them largely separated by a dog gate, but he'll
dissappear completely, or sit on one side and glare while she amuses herself
on the other, oblivious to his very presence.  We've been allowing for
supervised interaction for a few hours in the evenings, but that is always
unpredictable- some nights, they'll both nap on opposite side of the room,
others, the cat will glare and hiss while the kitten plays with a toy.

In case someone asks, we have 3 litter boxes now: one in the laundry room
downstairs, one upstairs, and a small one in the bathroom the kitten is
temporarily restricted to while we're at work.

Anyone have any thoughts/advice?  I figured the cat wouldn't be thrilled
from the outset, but I figured he would have cooled at least a little by
now.  Have I just not waited long enough?  Are we beyond hope?

thanks