XWiki Objects' number field values are not preserved in previous versions of a page in case of object deletion

When retrieving previous versions of a page, object's numbers are re-arranged if objects are deleted.
For example, let's suppose I have the following history:

Version X: Objects

{ C[0], C[1], C[2] }

Version X+1: Objects

{ C[0], C[2] }
Version X+2: Objects { C[0], C[2] }

If I rollback to X+1 then object numbers are rearranged in the following way:

Version X+3: Objects

{ C[0], C[1] }

This is a big problem because object's id are implicitly changed and, thus, their identity is not traceable anymore.