Copying files with dired preserving structure

[Alberto Luaces <aluaces@udc.es>]

Hi,

I want to classify some files contained in a directory hierarchy into
several groups, depending on their content.

So far I do a 'find-dired' to get a list of the available files and then
I mark each group by grepping into the files
(dired-mark-files-containing-regexp).

The problem is that if I try now to move those files elsewhere, the
hierarchy is lost, and besides that, files with the same name are
overwritten.

I have tried to "tar" the marked files to preserve the hierarchy, but
this approach is somewhat fragile, as I tend to use incorrect tar flags
and I risk corrupting my work when updating some of those "groups".

I am looking for a way to move marked files to a different place
preserving the directory structure with dired.

Thanks,

-- 
Alberto