RAD publishing problem and corba errors

I was deploying an application in rad 7 and was 6.1 server. I received below mentioned error. It took lot of time to figure some changed virtualHostName entry
in ibm-web-bnd.xmi to some random name from default_host. This should always be default_host.

Error:
Publish failed with errors, warnings or both. Please see server logs for more details.
Application Failed to Start. xxxxEAR
CORBA MARSHAL 0x4942f89a No; nested exception is:
org.omg.CORBA.MARSHAL: Unable to read value from underlying bridge : Mismatched serialization UIDs : Source (RepId RMI:java.lang.Throwable:F8678B4F4D2EB705:D5C635273977B8CB) = D5C635273977B8CB whereas Target (RepId RMI:com.ibm.ws.webcontainer.exception.WebAppNotLoadedException:2E921E9DEB124A7F:2D33383134313233) = 2D33383134313233 vmcid: IBM minor code: 89A completed: No
CORBA MARSHAL 0x4942f89a No; nested exception is:
org.omg.CORBA.MARSHAL: Unable to read value from underlying bridge : Mismatched serialization UIDs : Source (RepId RMI:java.lang.Throwable:F8678B4F4D2EB705:D5C635273977B8CB) = D5C635273977B8CB whereas Target (RepId RMI:com.ibm.ws.webcontainer.exception.WebAppNotLoadedException:2E921E9DEB124A7F:2D33383134313233) = 2D33383134313233 vmcid: IBM minor code: 89A completed: No
Please see server logs for more details.

less no of database connections and Multithreading

We have a Multithreaded application that is 10 year old. It worked fine for all those years suddenly it was too slow. The reason was while threads are created database connections are fully used and threads had wait on each other for the resource. The database configurations are defined in application for data source. It had max connections of 3 and min of 1. we changed the maximum connections to 30. it worked like a charm.

The type oracle.jdbc.driver.OracleTypes is not visible

I was working on migrating a project from WAS 5 to WAS 7. I experienced an issue with oracletypes class . The issue was type oracle.jdbc.driver.OracleTypes is not visible .
After doing hours of research looks like the WAS 7 uses oracle 11g driver. In ojdbc14.jar the visibility of OracleTypes is public the visibility of the OracleTypes class in ojdbc6.jar is changed to default so you can use it. We had to change to oracle.jdbc.OracleTypes from oracle.jdbc.driver.OracleTypes to make the application work.