Ext.override(Ext.data.HttpProxy, {
 
    doRequest : function(action, rs, params, reader, cb, scope, arg) {
        var  o = {
            method: (this.api[action]) ? this.api[action]['method'] : undefined,
            request: {
                callback : cb,
                scope : scope,
                arg : arg
            },
            reader: reader,
            callback : this.createCallback(action, rs),
            scope: this
        };
        
        if (params.jsonData) {
            o.jsonData = params.jsonData;
        } else if (params.xmlData) {
            o.xmlData = params.xmlData;
        } else {
            o.params = params || {};
        }
        /* tem que excluir esses parametros, para ele nao mandar corpo no request */
        if(this.api[action]['method'].toLowerCase() == "delete") {
          delete o.params;
          delete o.jsonData;
        }

        this.conn.url = this.buildUrl(action, rs);

        if(this.useAjax){
            Ext.applyIf(o, this.conn);
            if (this.activeRequest[action]) {
            }
            this.activeRequest[action] = Ext.Ajax.request(o);
        }else{
            this.conn.request(o);
        }
        this.conn.url = null;
    }

});