[TYPO3-english] TYPO3 Fatal Error: Extension key "lang" was NOT loaded!

[Tomiţă MILITARU]

Hi,
I was creating  a new page in the Typo3 backend and I got this error
message:
TYPO3 Fatal Error: Extension key "lang" was NOT loaded!
(t3lib_extMgm::extPath)

Since then, I can't access the backend, but the site is up and running.

I've looked in localconf,php for that extension, but no extension is with
that name (lang).
Please, can someone help me with this, I need to make some changes urgently.
Thank you.

-- 
Tomiţă MILITARU
AIESEC Sibiu Member
Board Member SbLUG
Junior Web Developer
Tel. +40741064681