更改oracle forms语言
The answer is given in this tutorial: http://www.yunning.net/blog/?p=252&cpage=1#comment-481

####After installation, if you would like to work in English environment, please change the “NLS_LANG” item in the register file with the path of “Root>HKEY_LOCAL_MACHINE>Software>Key_DeveSuiteHome_1″ (Supposed that your home name is DeveSuiteHome_1) to “AMERICAN_AMERICA.WE8MSWIN1252”3333

hope it will help you.
It works for me, I changed language from french to english.