This is damn ugly patch if you need to update it, see PHP_5_2 branch version to
understand what this patch is supposed to do as in 5.3 the ini section is
enabled only if mysqlnd driver is enabled which makes the contexts really
small.

--- php-5.3.1/ext/pdo_mysql/mysql_driver.c~	2010-02-20 01:08:04.000000000 +0200
+++ php-5.3.1/ext/pdo_mysql/mysql_driver.c	2010-02-20 01:08:52.982186037 +0200
@@ -436,6 +436,7 @@
 	pdo_mysql_db_handle *H;
 	int i, ret = 0;
 	char *host = NULL, *unix_socket = NULL;
+	char *connect_charset = NULL;
 	unsigned int port = 3306;
 	char *dbname;
 	struct pdo_data_src_parser vars[] = {
@@ -731,6 +731,12 @@
 		password_len = strlen(dbh->password);
 	}
 
+	connect_charset = PDO_MYSQL_G(connect_charset);
+
+	if (connect_charset != NULL) {
+		mysql_options(H->server, MYSQL_SET_CHARSET_NAME, connect_charset);
+	}
+
 	if (mysqlnd_connect(H->server, host, dbh->username, dbh->password, password_len, dbname, dbname_len,
 						port, unix_socket, connect_opts, PDO_MYSQL_G(mysqlnd_thd_zval_cache) TSRMLS_CC) == NULL) {
 #else
--- php-5.3.1/ext/pdo_mysql/pdo_mysql.c	2010-02-20 02:06:52.781846977 +0200
+++ php-5.3.1/ext/pdo_mysql/pdo_mysql.c	2010-02-20 02:06:52.781846977 +0200
@@ -44,10 +44,13 @@
 # endif
 #endif
 
+#endif /* PDO_USE_MYSQLND */
+
 
 /* {{{ PHP_INI_BEGIN
 */
 PHP_INI_BEGIN()
+#if PDO_USE_MYSQLND
 #ifndef PHP_WIN32
 	STD_PHP_INI_ENTRY("pdo_mysql.default_socket", PDO_MYSQL_UNIX_ADDR, PHP_INI_SYSTEM, OnUpdateString, default_socket, zend_pdo_mysql_globals, pdo_mysql_globals)
 #endif
@@ -55,9 +58,10 @@
 	STD_PHP_INI_ENTRY("pdo_mysql.debug",	NULL, PHP_INI_SYSTEM, OnUpdateString, debug, zend_pdo_mysql_globals, pdo_mysql_globals)
 #endif
 	STD_PHP_INI_ENTRY("pdo_mysql.cache_size",			"2000",	PHP_INI_SYSTEM,		OnUpdateLong,		cache_size,			zend_pdo_mysql_globals,		pdo_mysql_globals)
+#endif
+	STD_PHP_INI_ENTRY("pdo_mysql.connect_charset",	NULL,	PHP_INI_ALL,	OnUpdateString,	connect_charset,	zend_pdo_mysql_globals,	pdo_mysql_globals)
 PHP_INI_END()
 /* }}} */
-#endif
 
 /* true global environment */
 #ifdef PDO_USE_MYSQLND
@@ -69,9 +73,7 @@
  */
 static PHP_MINIT_FUNCTION(pdo_mysql)
 {
-#if PDO_USE_MYSQLND
 	REGISTER_INI_ENTRIES();
-#endif
 
 	REGISTER_PDO_CLASS_CONST_LONG("MYSQL_ATTR_USE_BUFFERED_QUERY", (long)PDO_MYSQL_ATTR_USE_BUFFERED_QUERY);
 	REGISTER_PDO_CLASS_CONST_LONG("MYSQL_ATTR_LOCAL_INFILE", (long)PDO_MYSQL_ATTR_LOCAL_INFILE);	
@@ -101,8 +103,8 @@
 	php_pdo_unregister_driver(&pdo_mysql_driver);
 #if PDO_USE_MYSQLND
 	mysqlnd_palloc_free_cache(pdo_mysqlnd_zval_cache);
-	UNREGISTER_INI_ENTRIES();
 #endif
+	UNREGISTER_INI_ENTRIES();
 
 	return SUCCESS;
 }
@@ -133,9 +135,7 @@
 #endif
 	php_info_print_table_end();
 
-#ifdef PDO_USE_MYSQLND
 	DISPLAY_INI_ENTRIES();
-#endif
 }
 /* }}} */
 
@@ -182,11 +182,14 @@
 }
 /* }}} */
 
+#endif /* PDO_USE_MYSQLND */
+
 
 /* {{{ PHP_GINIT_FUNCTION
  */
 static PHP_GINIT_FUNCTION(pdo_mysql)
 {
+#if PDO_USE_MYSQLND
 	pdo_mysql_globals->mysqlnd_thd_zval_cache = NULL; /* zval cache */
 	pdo_mysql_globals->cache_size = 0;
 #ifndef PHP_WIN32
@@ -196,10 +199,10 @@
 	pdo_mysql_globals->debug = NULL;	/* The actual string */
 	pdo_mysql_globals->dbg = NULL;	/* The DBG object*/
 #endif
+#endif /* PDO_USE_MYSQLND */
+	pdo_mysql_globals->connect_charset = NULL;
 }
 /* }}} */
-#endif
-
 
 /* {{{ pdo_mysql_functions[] */
 const zend_function_entry pdo_mysql_functions[] = {
@@ -242,15 +245,11 @@
 #endif
 	PHP_MINFO(pdo_mysql),
 	"1.0.2",
-#if PDO_USE_MYSQLND
 	PHP_MODULE_GLOBALS(pdo_mysql),
 	PHP_GINIT(pdo_mysql),
 	NULL,
 	NULL,
 	STANDARD_MODULE_PROPERTIES_EX
-#else
-	STANDARD_MODULE_PROPERTIES
-#endif
 };
 /* }}} */
 
--- php-5.3.1/ext/pdo_mysql/php_pdo_mysql_int.h~	2009-10-14 16:51:25.000000000 +0300
+++ php-5.3.1/ext/pdo_mysql/php_pdo_mysql_int.h	2010-02-20 02:04:48.918516081 +0200
@@ -61,8 +61,8 @@
 #include "ext/mysqlnd/mysqlnd_debug.h"
 #endif
 
-#ifdef PDO_USE_MYSQLND
 ZEND_BEGIN_MODULE_GLOBALS(pdo_mysql)
+#ifdef PDO_USE_MYSQLND
 	MYSQLND_THD_ZVAL_PCACHE *mysqlnd_thd_zval_cache;
 	long          cache_size;
 #ifndef PHP_WIN32
@@ -72,10 +72,11 @@
 	char          *debug; /* The actual string */
 	MYSQLND_DEBUG *dbg;	/* The DBG object */
 #endif
+#endif /* PDO_USE_MYSQLND */
+	char          *connect_charset;
 ZEND_END_MODULE_GLOBALS(pdo_mysql)
 
 ZEND_EXTERN_MODULE_GLOBALS(pdo_mysql);
-#endif
 
 #ifdef ZTS
 #define PDO_MYSQL_G(v) TSRMG(pdo_mysql_globals_id, zend_pdo_mysql_globals *, v)