Probleme upper accents

Hi, On my application PHP with Oracle database, all work fine with Oracle9i client, but when I test with Oracle11gR2 client I get warning with PDO driver. *Warning*: PDOStatement::fetch() [function.PDOStatement-fetch <http://vanves23/function.PDOStatement-fetch>]: column 0 data was too large for buffer and was truncated to fit it in with this request " SELECT DISTINCT UPPER(SUBSTR(NOM, 1, 1)) AS INITIALE, NOM

                               FROM MY_TABLE ORDER BY INITIALE ";

The field NOM contain in first character upper character with accent like this É Î Here are my configuration : - Apache2.2.21 - Php-5.1.4 with PDO Oracle - Client Oracle 11.2.0.1 - Base Oracle 11.2.0.1 On my Web server, I have set : ORACLE_BASE ORACLE_HOME TNS_ADMIN NLS_LANG = French_France.WE8ISO8859P1 LC_ALL=fr_FR LC_COLLATE=fr_FR.ISO8859-1 LC_CTYPE=fr_FR.ISO8859-1 LC_MESSAGES=fr LC_MONETARY=fr_FR.ISO8859-1 LC_NUMERIC=fr_FR.ISO8859-1 LC_TIME=fr_FR.ISO8859-1 In HTML headers of page, there is <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="fr" lang="fr"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> And on my Oracle Dababase server, I have NLS_CHARACTERSET=WE8ISO8859P15 NLS_NCHAR_CHARACTERSET= AL16UTF16 How I can suppress these warnings ? Thanks for your help.