Problem validating connections from connection pool

I'm using MySQL on a Tomcat server with the DBCP connection pool.

I'm having trouble setting up the connection pool such that it will
validate connections. I initialized the connection pool object in an
xml file like this -

<bean id="my-datasource"
class="org.apache.commons.dbcp.BasicDataSource" destroy-
method="close">
<property name="driverClassName"
value="com.mysql.jdbc.Driver" />
<property name="url" value="${jdbc.url}"/>
<property name="username" value="${jdbc.username}"/>
<property name="password" value="${jdbc.password}"/>
<property name="initialSize" value="4"/>
<property name="maxActive" value="400"/>
<property name="maxIdle" value="40"/>
<property name="poolPreparedStatements" value="true"/>
<property name="validationQuery" value="select 1"/>
<property name="testOnBorrow" value="true"/>
</bean>

To test it, I start Tomcat and run a few queries. Then I stop and
restart my MySQL server, then I try to run the queries again. What I'm
expecting to happen is that the connection pool will realize that the
old connections don't work again and discard them before they're ever
returned to my application. Instead, my application gets the bad
connections and errors out trying to use them. This happens
indefinitely until I restart Tomcat.

I also tried using a query that actually queries a real table in my
database, but that did not help.

Is there something wrong with my configuration? This seems like a
pretty simple and straightforward thing that should work with no fuss.

Thanks,
Frank