Do not expand symbolic links when storing undofile

Question

Is it possible to keep the path to a symbolic link instead of the original file when storing an undofile?

For example, assume I have the following symbolic link:

~/.vimrc -> ~/Dropbox/Backup/Dotfiles/.vimrc

When I edit the ~/.vimrc file, my undofile looks like this:

%Users%username%Dropbox%Backup%Dotfiles%.vimrc

But I like the undofile to look like this:

%Users%username%.vimrc