Q:

GPL and closed-source licensing for selling my script

I am working on a PHP script that I plan to sell without giving the user the ability to distribute it to anyone else.
I have heard about GPL being viral and I have quite a few libraries that are being used in my script that are under the GPL. (for example : jquery, phpthumb etc)
Does this mean that if a user who has bought my code can freely distribute it because a part of my code is under GPL so it becomes viral and my whole project becomes GPL ? 
Can i not use any GPL code in my project ?
Thanks for any help.

A:

If you use GPL code in your project, you have to release it under the GPL license. For more informations, see http://www.gnu.org/copyleft/gpl.html.
However, JQuery is also licensed under the MIT license, which is more permissive, and you can purchase a commercial license for phpThumb.

