Administrator Cannot See Administration Toolbar, Buttons And Shortcuts On Report Manager

Hy everybody.

I have recently installed from scratch RS 2003 on a WIN2003 SRV and got that the problem that the administrator cannot access or even see the regular administration toolbar and links at the Report Manager, such as Site Configuration, Upload New File, the common 'Contents | Properties ' tab, among other stuff. The only options available are 'Home', 'My Subscriptions' and 'Help', in the right superior link bar. I find this behaviour very strange, since the RS comes right out of the box configured with full access to administrator, but right now I CAN'T do any administration task on the RS Server.

Another strange behaviours I've found:
- The few links that appear redirect to the internal ip address of the server.
- When you call the '/ReportServer/ReportingService.asmx' it returns an XML document, not the usual browsing interface.

There's some information about the server configuration I think it might help:
- IIS is running more than one website, and the RS server is not installed on the Default WebSite, wich is stopped.
- SharePoint Services is running in the server, but not in the DefaultWebSite.
- The security settings of the virtual directory of the Report Manager are configured to use Windows Authentication and are NOT configured to use anonymous authentication.
- The server is published to the Internet.

There's some stuff that I tried and for now didn't worked:
- Create the virtual directories in other websites.
- Switch the attributes of the 'impersonate' attribute in Web.config file between true and false.
- Enable anonymous authentication and use the administrator account to impersonate.
- The steps described in the help article 'Troubleshooting a Side-by-Side Installation of Reporting Services and Windows SharePoint Services'
- Reinstalling the RS product.

I really hope you guys can help me with this.

Thanks in advance.
JC