Thread:Project:Support desk/Changing the structure of page’s table of contents

I have encountered following problem – how can we make the Mediawiki to add a dot in TOC numeration after each digit? Explanation: now the standard numeration of headings looks like:

1 Text 2 Text 2.1 Text 2.2 Text

And we need

1. Text 2. Text 2.1.   Text 2.2.   Text

If you have any ideas about solving this problem, I would be very grateful to you for any help. The task is actual because all the contents in books have dots in numeration.