java.lang.UnsatisfiedLinkError: no ojdbc14 in java.library.path

This month I am logging only the errors
I am setting up a backup of a working application, where I came across the previous errors. Here is another one.
java.lang.UnsatisfiedLinkError: no ojdbc14 in java.library.path
Let me tell you the environment,
I have the application, whose lib folder contains class12.jar and ojdbc14.jar. Both the jars are in classpath, then I replaced this ojdbc14.jar of the application with the ojdbc14.jar from the local oracle installation folder. That doesnt solve the issue, later i need to replace classes12.jar also. That application lib folder files are working fine for Oracle 9i. but not for 10g. So, this is basically a version incompatibility.