problem installing php4.0.6 on windows nt 4

dear all, i am new here, because i experienced a lot of problems when installing php4 (or php3) on a windows nt 4 server. actually, my society is running its intranet servers on windows nt4 service pack 5 (iis3) where i have to rebuilt the intranet. as i am running php/mysql on the website (apache 1.3.19 / hp/ux 11) i thought to install the same on the intranet. my own server is a windows 2000 server which one i didn't have problem but with nt4, it goes wrong. well, i tried to install php3 on a test server (service pack 6) which happened well. i then installed php3 on the production server (service pack 5), but it didn't work. when i try to access a php page, i can't view it through the browser, and a DOS window is opening where the script is executed. i changed the registry, but it didn't change anything. so i have just installed a new server in my office where i put windows nt4 service pack 5, then service pack 6, but it didn't work. i then decided to install php4.0.6 with the automatic installer, and everything goes well. i didn't encounter any problem with php4.0.6 and mysql 3.23.30, with the exception i had have to declare the variables before to use them. but it was okay for me. as i wanted to have a clean server, i reinstall windows nt4 service pack, then reinstall php4.0.6 in the same way, but it does work anymore. i have the same problem as before, ie, when i access a php page through the browser, it runs a DOS window where it execute the script. i have check the registry, but all his okay. the problem run the same way with service pack 6. so i don't understand. anyone there with the same kind of problem ? anyone to tell what goes wrong ? thanks for your help. pascal. ps/ sorry for my english, i just french ;-)