Do I have to deliver my utility and helper code to clients?

Question

Over the years I've created a bunch of Java utility and helper libraries which I just attach to new projects. Then, when I deliver code to my clients, I send all the code except for the libraries themselves (not JARs but source code files).

A client complained that he could not compile the project as some libraries were missing. I tried explaining him about my own libraries, but he was not satisfied.

How do you handle such situations? I am still apporting changes to these libraries often and I cannot compile JARs each time I start working on some new project. How to overcome this issue - not to share private libraries (personal intellectual property) and have happy clients?