You could convert it to a photoshop raw format (keep track of image width and height) and then upload it to Gigapan.org, their uploader supports very large photoshop raw files.
From there, it is possible, through some effort I have documented at forum.gigapan.org, to use your image with krpano. (hint: you will need to make a image proxy server).
or you could also run the Gigapan uploader to your own server and use krpano directly (it supports the Gigapan file schema, but Gigapan does not have a crossdomain.xml policy, so you can't use krpano directly)
At the forum.gigapan.org, I have posts showing how to set up your own reciever for the Gigapan uploader, so you can use the Gigapan uploader to break apart your photoshop raw file and convert it to a useable format for krpano.
This is all more complicated than it should be, but it is a fully working solution.
Cheers.
Jason B
(odyssey on forum.gigapan.org)