Many default.aspx on one IIS Server

[BBoule]

Hi

I've some IIS virtual servers on my physical server and on every Virtual server, I have a WSS site

As I've read, it's not good to modify a page with FrontPage, so I decide to modify directly the file default.aspx in the directory :
c:\Program Files\Common Files\Microsoft Shared\web server extensions\60\TEMPLATE\1033\STS

But my problem is that it modify all pages default.aspx on all sites

Does someone has an idea????

Many Thx