Error 400 on iFrame when using a different DNS?

Hi guys! We're in a situation where we really don't understand the problem.

Here's the scenario.

We have two Java applications. Application1 contains two iFrames, the left side

having all the links and the right side where pages you clicked on the links(the

left iFrame) is loaded.

One of the links in the iFrame constains an anchor, to another application. This

seems to work fine.

These two applications reside in the same IP address and can be accessed through

the web browser via

http://xxx.xxx.xxx.xxx/application1

and

http:xxx.xxx.xxx.xxx/application2

they also have the following domain names, respectively.

http://myhome.mydomain.ph

http://rpc.mydomain.ph/application2

this seems to work fine, until we tried to access http://rpc.mydomain.ph in

another DNS.

The other DNS name is yourdomain.ph. yourdomain.ph has the same IP address as

mydomain.ph, and is actually just pointing to mydomain.ph. So basically,

yourdomain.ph is also mydomain.ph.

The real problem:

When yourdomain.ph is accessed, you can still actually load

rpc.mydomain.ph/application2. The problem is that any link I access in rpc.mydomain.ph/application2(rpc.mydomain.ph/application2 is first loaded successfully in the iFrame) gives

an http error 400 message. All links in application 2 are relative to the application

which really makes us bang our heads. Do you guys have any ideas on why we're

encountering this problem? Thanks!
[ January 29, 2007: Message edited by: Timothy Sam ]

Hi Tim,
what I guess is, whenever you are trying access your original domain, the "yourdomain" thing is acting like a proxy. It happens with some proxy as they understand the HTTP headers in a different way, as well as the Server Response from your domain back to the PROXY. Please check your Application server, what exactly it's throwing as error. Do mind your HTTP request/response headers, 'cauz we had once encountered with this sort of problem.

Subhadip Chatterjee

Thank you for your response! What goes on the server is just a pass-through a Servlet then the servlet forwards/includes to a JSP. This seems to happen only in IE 6 and 7 but not in Firefox 2. BTW, clicking on a link would make a call to:

location.href = url;

Thank you for your response! I hope to hear more ideas.