Extracting qooxdoo SDK on Mac shows similar file but different case

I noticed that when I try to extract qooxdoo on a Mac machine it "unzip" gives the following prompt

inflating: qooxdoo-1.3-sdk/framework/api/script/qx.ui.groupbox.RadioGroupBox.json  
inflating: qooxdoo-1.3-sdk/framework/api/script/qx.ui.indicator.ProgressBar.json  
replace qooxdoo-1.3-sdk/framework/api/script/qx.ui.indicator.Progressbar.json? [y]es, [n]o, [A]ll, [N]one, [r]ename: error:  invalid response [s]
replace q开发者_StackOverflow中文版ooxdoo-1.3-sdk/framework/api/script/qx.ui.indicator.Progressbar.json? [y]es, [n]o, [A]ll, [N]one, [r]ename: 

It looks like there are two files that's similar as far as HFS file system is concern --- that is qx.ui.indicator.ProgressBar.json and qx.ui.indicator.Progressbar.json

Has anyone able to extract the SDK on a Mac before?

In fact, you've found an artifact in the qooxdoo 1.3 archive! The two files are basically identical, but please retain the "ProgressBar" (upper-case "B") variant and discard the other, as this gets referenced elsewhere. - Which OSX version are you running?