Datasource for Tomcat 4.1 and Sybase

[giri pal]

I am using Tomcat as application server and Sybase as DB.
I recently migrated my application Tomcat 4.0xx to 4.1 and wanted to use the datasource/connection pool.I use JConnect (JConn2.jar) for the JDBC driver and it works fine in Tomcat 4.0.
IS there any body that uses Tomcat 4.1 and sybase? can you explain me please? or post a sample working code
here is what i did:
1)I have placed the JConn2.jar under $CATALINA_HOME/common/lib
2)In my server.xml I have modified
<GlobalNamingResources>
<Environment name="simpleValue" override="true" type="java.lang.Integer" value="30"/>
<Resource name="jdbc/TestDB" scope="Shareable" type="javax.sql.DataSource"/>
<Resource auth="Container" description="User database that can be updated and saved" name="UserDatabase" scope="Shareable" type="org.apache.catalina.UserDatabase"/>
<ResourceParams name="jdbc/TestDB">
<parameter>
<name>validationQuery</name>
<value></value>
</parameter>
<parameter>
<name>maxWait</name>
<value>5000</value>
</parameter>
<parameter>
<name>maxActive</name>
<value>2</value>
</parameter>
<parameter>
<name>password</name>
<value>xxxx</value>
</parameter>
<parameter>
<name>url</name>
<value>jdbc:sybase:Tds:localhost:3000</value>
</parameter>
<parameter>
<name>driverClassName</name>
<value>com.sybase.jdbc2.jdbc.SybDriver</value>
</parameter>
<parameter>
<name>maxIdle</name>
<value>2</value>
</parameter>
<parameter>
<name>username</name>
<value>xxxx</value>
</parameter>
---------------------------------------------
3)AND in my web.xml

<resource-ref>
<description>DB Connection</description>
<res-ref-name>jdbc/TestDB</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
<res-auth>Container</res-auth>
</resource-ref>

4) when i run the application I get the following error:
java.sql.SQLException: Cannot load JDBC driver class 'null'
at org.apache.commons.dbcp.BasicDataSource.createDataSource(BasicDataSou
rce.java:529)
at org.apache.commons.dbcp.BasicDataSource.getConnection(BasicDataSource
.java:312)

[giri pal]

Still looking for an answer. Can any one help me?