question about jnlp (java web start)

Hi,

I created a jnlp file, a jar file and a html on my local disk.
Clicking the link of jnlp from the webpage, my Java Web Start
launches.
Everything is ok.

But after I've uploaded all the files to the webserver, my browsers
(Mozilla and IE) everytime just read and display the plain text in
jnlp file. The Web Start never launches. (The permission for all the
files is 755.)

Anyone know why?

Thanks a lot !!!
roy