Funny renaming problem

I‘m not sure if this belongs to iOS or if it is an IDE problem, but as I encountered it in an iOS project:

I made an extension module for UIScrollView functionalities in iOSTextAreas. As these functions are used in iOSTables too, I copied the module and saved it in another project.
There I renamed it to iOSTableExtension and tried to re-import it to the main project via drag & drop.
When I do so, it gets its original name again replacing the iOSTextAreaExtension module which it stems from, so I’m not able to hold both in a common project and redesign the getter/setter functions so they work with a table.
Is this a known problem? With some workarounds?