Viewers will not show you masks, since they cannot be manipulated in them. Now, when you open the file in PhotoDeluxe select the background solid colour (if it has some kind of magic wand select tool) and invert this selection. So now the hair is selected. I don't know if it will come out the same, as I get it already masked but you can try it and see if the edges come out alright. Otherwise, you'll have to have a look at the Paul Hafeli tutorial and make your own transparency map and use the files within Poser on the square.