I was using a InkScape on my Mac for whole day & after a meanwhile closing it & reopening it I found that copy pasting is not working correctly,
i.e. Copying one vector object from one file & pasting it in another file converts that vector object to Bitmap & another thing that was not working was ‘Paste In Place’
But I now found workaround to that problem,
Disabling ‘Sync PasteBoard’ Functionality within X11 (Which is Included in XQuartz App for OSX Mountain Lion) solves the problem of converting vector object to Bitmap after pasting the same object in another SVG file.
Do This (Go to): X11 > Click on ‘Preferences’ tab > Choose ‘Pasteboard’ tab > Uncheck ‘Enable Syncing’
It should solve the problem.
Thanks & Regards