It's part of the mainline ESB code. So if you're picking up SQLTableGatewayListener, it should be there too.
I pulled the source code for SqlTableGatewayListener from the .src library and put it into my project with a new name but it will not compile because the above file is not in the build path.
I am trying to find out what jar file I am missing from my build path.
It's part of the main ESB code. If you can resolve Message, then you should have it in your classpath. Check out the trunk and you'll see.