Jenkins: All post-build actions appear twice - no SVN tagging

We have some Jenkins (was formerly a Hudson system) jobs running. Now, we saw that all of a sudden most of the post build actions appear twice:

Additionally, if Subversion tagging for successful build is selected, it won't do the tagging anymore because it's deselected again and the input fields go back to default if co开发者_运维问答nfiguration is reopened (no matter if one or both of the same post build action is selected).

Has anyone had this strange behaviour as well and can tell me how to get rid of it?

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Since I had the problem again, I'd like to add my previously stated comment as answer - after updating all plugins, the problem was solved and every option was listed only once.