I recently install Oracle10g and JakartaTomCat and i can run sql statemenst from my JSP page. In fact, i read many webpages examples with MySQL using only the sql tags, making more usefull.

How can i make it whit Oracle? I need more configuration in server.xml, context.xml or web.xml?

In web.xml i have this:
<resource-ref>
        <description>Fuente de datos Oracle10g en servidor linkamarillo</description>
        <res-ref-name>jdbc/oracleInLinkamarillo</res-ref-name>
        <res-type>javax.sql.DataSource</res-type>
        <res-auth>Container</res-auth>
    </resource-ref>

In $CATALINA_HOME/conf/server.xml:
<Resource
                        name="jdbc/oracleInLinkamarillo"
                        auth="Container"
                        type="javax.sql.DataSource"
                        driverClassName="oracle.jdbc.driver.OracleDriver"
                        factory="org.apache.tomcat.dbcp.dbcp.BasicDataSourceFactory"
                        url="jdbc:oracle:thin:@server:9999:SID"
                        username="xxx"
                        password="xxx"
                        maxActive="20"
                        maxIdle="10"
                        maxWait="-1"/>

In $CATALINA_HOME/conf/context.xml:
<ResourceLink global="jdbc/oracleInLinkamarillo" name="jdbc/oracleInLinkamarillo" type="javax.sql.DataSource"/>

I using this code:
<sql:query var="rs" dataSource="jdbc/oracleInLinkamarillo">
select id, descripcion, vigencia, periodo from prm_validaciones
</sql:query>

  <h2>Results con la etiqueta sql</h2>

<c:forEach var="row" items="${rs.rows}">
    Clave Id: ${row.id}<br>
    Descripcion: ${row.descripcion}<br>
    Vigencia: ${row.vigencia}<br>
    Periodo: ${row.periodo}
</c:forEach>

... and the result in screen is this:
Clave Id: ${row.id}
Descripcion: ${row.descripcion}
Vigencia: ${row.vigencia}
Periodo: ${row.periodo}

How can i use sql tags with a Oracle context?

thks.

The JSTL SQL tags work just fine with Oracle see:
http://www.oracle.com/technology/products/jdev/tips/schalk/jstl_sql/jstl_sql.html for example. You might try setting the datasource up directly in the page to make sure that that works - then move on to using a JNDI lookup.