It's true. There are certain scenarios that can come up in which you have to call Microsoft for support. Should such a scenario arise within your SharePoint environment, be aware that Microsoft may not be able to support you at all...particularly if you've customized the SharePoint configuration/content databases in some way other than using a web browser, SharePoint Designer, or Visual Studio to program against the SharePoint API. The following is a great link that provides more detail.
Support for changes to the databases that are used by Office server products and by Windows SharePoint Services --> this also applies to all flavors of SharePoint 2010.
For your convenience, here's a SnagIt screen capture of those things that Microsoft does not want you to do to your SharePoint environment. Can you do these things? Yes. Should you? Nope. If you do, then later call Microsoft support for assistance with some issue that you're having (even if it has nothing to do with any of these changes you've made), Microsoft will force you to undo these customizations before supporting you.
If you perform any of these actions, you run the risk of losing Microsoft's support for your SharePoint environment.
The old adage: just because you can doesn't always mean that you should.