Application redeployment problem

[jay denzel]

Hi,
I am redeploying a web application using the application manager.
I invoke the manager using ant. Everytime I redeploy an application which
has resources in JNDI I get the following exception thrown.

javax.naming.NamingException: Cannot create resource instance
        at org.apache.naming.factory.ResourceEnvFactory.getObjectInstance(ResourceEnvFactory.java:146)
        at javax.naming.spi.NamingManager.getObjectInstance(NamingManager.java:301)
        at org.apache.naming.NamingContext.lookup(NamingContext.java:838)
        at org.apache.naming.NamingContext.lookup(NamingContext.java:185)
        at org.apache.naming.NamingContext.lookup(NamingContext.java:826)
        at org.apache.naming.NamingContext.lookup(NamingContext.java:185)
        at org.apache.naming.NamingContext.lookup(NamingContext.java:826)
        at org.apache.naming.NamingContext.lookup(NamingContext.java:185)
        at org.apache.naming.NamingContext.lookup(NamingContext.java:826)
        at org.apache.naming.NamingContext.lookup(NamingContext.java:198)
        at org.apache.naming.SelectorContext.lookup(SelectorContext.java:183)

During the startup of the application I set references I get from JNDI on several beans this causes the exception.
I have the necessary entries in server.xml and web.xml
Everything is fine when I install the application and start the server then.
As soon as I redeploy the application while the server is running the above exception is thrown.
This happens both with Tomcat 4.x and 5.x.
Until now I did not come up with a solution.
Any ideas, or has anyone experienced the same problem?
Any help greatly appreciated.
Thanx,
jay