SQL Server 2005 Express Problem with Date format in transact sql

my database in in French language.
The collation of sql server 2005 is in French.

When i use sql manager and look inside the tables the dates are well diplayed
in french format dd/mm/aaaa but the queries don't work

If i type "select * from mytable where date_update is < '20/11/2005' " it tells me
that it can't convert in date a string.
I i type in my query '11/20/2005' it works fine and the rows display date in english format differently than the display i have by opening the tables with the manager.

Of course i want to use french format in the transact sql queries.

Thanks for your help.

Patrick

[650 byte] By [Patrick_msdn] at [2007-12-17]