Yeah, I remember that the creator and lead developer of SQLite once said that he wished he had chosen a proper license just because a lot of corporates raised issues due to the license.
(It was a weird issue that I had not come across before and that's why the licensing thing stuck in my mind).
I guess he found a way to fix it:
> The SQLite source code is in the public domain, and is free for use by anyone and for any purpose. No license is required. However, some users desire a license so that they can have warranty of title, or just because their company lawyers say they need one. A perpetual license and warranty of title for the core SQLite source code is available for this purpose.