There's a good stushie (pronounced stoo-she, a good Scots word for robust debate) going on at Joomla.

It looks like the Joomla developers have decided to ask all the developers with extensions that have proprietary licenses to remove them from the JoomlaForge because they violate the GPL conditions that Joomla is released under. Furthermore, there is a strong suggestion that commercial extensions MUST be released under GPL.

I reproduce the core argument here:

1. http://www.gnu.org/licenses/gpl-faq.html#GPLAndPlugins

If the program dynamically links plug-ins, and they make function calls to each other and share data structures, we believe they form a single program, which must be treated as an extension of both the main program and the plug-ins. This means the plug-ins must be released under the GPL or a GPL-compatible free software license, and that the terms of the GPL must be followed when those plug-ins are distributed.

2. http://www.gnu.org/licenses/gpl-faq....ereAggregation

Combining two modules means connecting them together so that they form a single larger program. If either part is covered by the GPL, the whole combination must also be released under the GPL--if you can't, or won't, do that, you may not combine them.

This means that installing/adding a component/module/plugin to Joomla! is creating a combined work, if the third party developer doesn't want to violate the GPL he will need to release the module/component/plugin under the GPL or GPL-compatible license. It also means that a third party developer cannot encrypt his extension, without also making the code available when distributing the extension (hence the term open source license).

So, guys and gals ..... what does this mean for Sugar extensions? ..... after all, as far as I'm aware, the difference between SPL and GPL is in the attribution clause.