We have a very small application and the code base is not very large plus its not a distributed architecture. Are there any popular alternative tools that tackle transaction management, caching, scalability issues that EJBs are suggested as a fix for?

Try JGrinder:

It's an object-relational mapping system that handles transactions well. It's being used in production by some very large companies.

http://jgrinder.sourceforge.net

It doesn't really have a SessionBean like component, but it's a good starting point. From my understanding of JGrinder, it "can" support transactions across objects without the objects necessarily being persistent objects, so you could probably create a sessionbean like layer...

Take a look at Avalon and Turbine and Cocoon at jakarta.apache.org

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