[Zope] How to use manage_clone right??

[Breitenreicher, Marc]

Hi, 
I've got a problem with the manage_clone function.

I used it several times before, but this time it's something special.
Normally you clone an object like this, where 'mydoc' is the the object and
'new_id' the new name of the cloned object:
<dtml-call "manage_clone(mydoc, 'new_id')">

In my special case, mydoc is not the object itself, but a string of the
objects name.
The function now can't clone, because mydoc (the string) is not an object
and returns the error message
AttributeError: cb_isCopyable

So how can I clone an object by calling the manage_clone function with the
variable 'mydoc'???

Thanks for help

Marc