Pushed it with that fix. I also added a further "data_" prefix, so it's "data_${name}_XXXX" now. Hopefully this is less problematic than yesterday's ...
t/004_timeline_switch....."remove_tree" is not exported by the File::Path module
remove_tree is only in File::Path 2.07 but Perl 5.8.8 has 1.08. No buildfarm member has complained, so clearly we don't actually test with the stated supported Perl version.
The attached patch fixes it to use the legacy File::Path interface 'rmtree' so master runs on 588 again.