If you develop BlackBerry software using RIM's BlackBerry Java plugin for Eclipse and use Subversion for version control, you could end up shipping your source code with your executable if you are not careful. I had hoped this would be solved with the new version (1.1) of the plugin -- still in beta -- but based on my experience with one of the betas this does not appear to be the case.
The problem comes from the plugin's naive handling of non-Java files. Subversion keeps a copy of every version-controlled file in your sandbox. For example, if you have a Foo.java you will also have a copy as .svn/text-base/Foo.java.svn-base. This allows you to do diffs with the base version or revert your changes without even contacting the SVN server. But when RIM's plugin builds your *.cod executable, it assumes those *.svn-base files are resource files to be bundled with your COD file. The result is that if you view your resulting COD file in a text viewer, you will see copies of your source files -- those svn-base files -- embedded in the binary. Good grief.
Until RIM fixes this, one way to work around this is to specifically tell Eclipse to omit those SVN support files from the build. In your project properties, go to Java Build Path, select the Source tab and edit the source folders' "Excluded" entries. You can use wildcards in your exclusion patterns. And of course, make a test build and view it to make sure your source code is really excluded.