[nickarls]

In that case I'm a bit confused what could be the cause

1. Same browser

2. Same Windows server host

3. Same JDK for server

4. Same DB/schema

5. Same DB drivers/module

6. Same APEX.war

7. Different AS server version

[mayerw01]

Did you check the URIEncoding?

But to prevent IDN Spoofing the browser should encode the special characters in the URLs. So I guess the behaviour in my environment is correct.

Which browser are you using? Maybe you check the related parameters.

I understand there had been an issue in Internet Explorer 7 that the 'Turn off sending URLs as UTF-8' setting was behaving in the opposite manner as described (Article ID: 925261).

Maybe the correction to this bug had been applied in between. So if you are using IE I would suggest to check this setting.