just uncomment this lines in libraries/database_interface.lib.php
if (! empty($GLOBALS['collation_connection'])) {
// PMA_DBI_query("SET CHARACTER SET 'utf8';", $link, PMA_DBI_QUERY_STORE);
//PMA_DBI_query("SET collation_connection = '" .
//PMA_sqlAddslashes($GLOBALS['collation_connection']) . "';", $link, PMA_DBI_QUERY_STORE);
} else {
//PMA_DBI_query("SET NAMES 'utf8' COLLATE 'utf8_general_ci';", $link, PMA_DBI_QUERY_STORE);
}
if you store data in utf8 without storing charset you do not need phpmyadmin to re-convert again the connection. This will work.