This is not necessarily true. It depends on the open source licenses that the other libraries are using. Something like the GPL you can include the open source library in your application and only need to release code for that library if you modified the library itself, but you are *not* required to release the code for your own application. Look at Oracle, they make heavy use of Apache web server in the ERP applications, but they are most definitely not open source.
A GPL-licensed library would absolutely require you to release the code for your entire application. An LGPL-licensed one would not. I don't know specifically much about the Oracle ERP applications, but if they are web apps, then they are completely separate from Apache anyway (compare a text file that you write with the editor that you wrote it in). Even so, Apache isn't GPL, it's licensed under the Apache license, so they may be able to do that anyway.
Having said all that, it doesn't matter what Oracle do. If the OP is just communicating via JSON with bitcoind, then licensing doesn't matter. It's when the code is taken and incorporated into a new product that the license matters. I don't know what s/he does or is planning on doing, but I just wanted to address the GPL comment...
If you have any questions/problems, let me know.
