Sun Microsystems, which acquired Open Source database firm MySQL in January, has apparently found the key to unlocking their plans to make some MySQL features commercial-only: torch-wielding users.

Word emerged last month that Sun/MySQL was considering limiting "advanced" features like encryption and backup compression to commercial customers, departing from MySQL's traditional stance of producing wholly-open software. Former MySQL, now Sun, execs swore the plan had been in place long before the buyout, but we — and a lot of others — thought it was a bit strange that the first word of making MySQL proprietary came three months after being bought by a company that frequently mixes open and closed technology.

The news was met with outrage from users, and apparently their voices were heard, as the company has done an abrupt about-face, with Community Relations VP Kaj Arnӧ declaring on the company's blog that MySQL "will always remain fully functional and open source" along with its connectors and storage engines. He specifically set out that in MySQL 6.0 — the version with the planned proprietary features — the backup, encryption, and compression features would be Open Source, abandoning the proposal to close them. The comments — which were peppered liberally with words like openness and change in bold — went on to re-iterate the earlier line about the change being hatched prior to Sun's buyout, and speaking about the need for commercial add-ons to support Open Source development.

While we're glad to see the change in Sun/MySQL's position about MySQL 6.0, the very last paragraph hints that this is merely a temporary respite, and that the proprietary push will be back. "[E]xpect Sun/MySQL to continue experimenting with the business model, and with what’s offered for the community and what’s offered commercial-only. We won’t always know the right answer..." Allow us to offer a bit of advice: When it comes to Open Source projects, locking the doors is rarely the answer.