Problem with the translation -adding new phrase

Hello to all,
How are you all doing?
 
Well,I'm trying to Translate eGroupWare and I came across with this message when I tried to add some new phrases in the TimeSheet Application.Till now,I added new phrases with no problem.Though now this message reared its ugly head..
 
Why is this happening???
 
This is the message :
 
Loading source langfile: en...
Loading target langfile: el...
 
Database error: Invalid SQL: INSERT INTO egw_lang (message_id,app_name,lang,content) VALUES ('exports entries from your timesheet into a csv file. csv means \'comma seperated values\'. however in the options tab you','can also choose other seperators.','en','en')
mysql Error: 1062 (Duplicate entry 'en-can also choose other seperators-exports entries from your ti' for key 1)
 
File:egroupware\phpgwapi\inc\class.translation.inc.php
Line: 645
Function: egw_db::insert / translation::install_langs / solangfile::loaddb / bolangfile::loaddb / uilangfile::edit / ExecMethod(developer_tools.uilangfile.edit)
 
Session halted.
 
AND THE LINE 645 IS THIS :
 
        ),False,__LINE__,__FILE__);
 
Thanks a lot in advance
 
Best Regards