Tabs in source code

A boring question, are tabs permitted by the formatters?
I did a fresh check out from master this week, and several projects in eclipse are complaining about files with tabs in the source, OG-Bloomberg, OG-Financial, OG-MasterDB, OG-Security, OG-Web. I happen to have AnyEditTools plugin installed also, as it helps stamp out tabs, although I think it is checkstyle that is complaining, but I am not sure.

We experienced the same problem recently with tabs in xml files. We believe it may be due to a new version of the checkstyle Eclipse plugin, but cannot be sure.

Tabs are explicitly disallowed (as an error) in our coding standards and checkstyle. However, this while this should apply to non-Java files, it has never been enforced, thus some tabs have crept in.

We found a way to solve the problem by making checkstyle only check Java files (which should have been the default option). The commit is in develop branch, so you can cherry pick it to your local master branch.
https://github.com/OpenGamma/OG-Platform/commit/a3795d6cc99bc904b523446bc694c4f307db25d3

ok, thanks
gary