[TYPO3-dev] Change the backend language in typo3 6.2.2

[Sejal]

Should I need to register here http://lists.typo3.org/cgi-bin/mailman/listinfo/typo3-english?

There is no error in error log. Typos3conf has 755 permission and also checked with giving it 777.
When I update from repository then some are not available and some shows Up to date. But the strange thing is that after updating it when I again click on language under admin tool, then again all extension shows that they are not checked and again I need to update it from repository.