Looks like I totally don't understand how python nose --match parameter works

By default --match parameter has value '(?:^|[b_./-])[Tt]est' which is fine (wait, no, I don't understand what that means). But if I want to run only test methods which start with a prefix '.*test_post_object_.*' (it is not a correct reg expression?), nose does not find anything and runs zero tests. Suppose I run nose in the same directory, where methods exist, and I know about -w parameter.

ps: And I could not find anything about nose testMatch, which is mentioned in the manual. This is so weird...