I am trying to embed a Javascript engine into my application. But the license for Mozilla Javascript engine is GNU/GPL/MPL based and I don't have the time and energy to digest the cryptic legal document.

In short, does the license mean I need to publish my application's source code if I embed the engine into my own appli.? Something I think is quite impossible but as what i understand from the CopyLeft license, any work derived from modifying the source code means the derived work must be made open source as well.