feature request and small bug for comparison screen

dear developers

feature request
---------------
for the lazy once like me: i would like to have some buttons on the  
comparison screen such as "delete" and "copy for editing", e.g. next to  
the headers "Older version (xx)" and "Newer version (xx)". isn't it  
best to decide to delete or reuse content when you actually see it? and  
add a link "back" like it is also available when viewing a old version  
(here, these buttons could be useful as well).

small bug
---------
i found also an unimportant bug with the comparison feature which  
appears in certain circumstances. to reproduce: 1. delete all versions  
except the two latest ones, 2. because there are only two versions left  
i click on select all (and spare myself one click, i'm lazy;-), 3.  
click on the compare button, and 4. then on the browsers back button. a  
panel tells me now "the page you are trying to view contains postdata  
that has expired from cache. if you resend the data, any action the  
form carried out (such as a search or online purchase) will be  
repeated. to resend the data, click ok. otherwise, click cancel." when  
clicking on ok i get a zope error:

   Error Type: BadRequest
   Error Value: 0 does not exist

(0 being the oldest version available for this document previous of the  
deletion step 1 above.)

traceback below. the error occurs only the very first time and it has  
nothing to do with my laziness; it doesn't depend on how i select the  
versions to be compared. this must be some caching issue...

regards,
marc




Error Type: BadRequest
Error Value: 0 does not exist

Traceback (innermost last):
   Module ZPublisher.Publish, line 101, in publish
   Module ZPublisher.mapply, line 88, in mapply
   Module ZPublisher.Publish, line 39, in call_object
   Module Products.FileSystemSite.FSPythonScript, line 104, in __call__
   Module Shared.DC.Scripts.Bindings, line 306, in __call__
   Module Shared.DC.Scripts.Bindings, line 343, in _bindAndExec
   Module Products.FileSystemSite.FSPythonScript, line 160, in _exec
   Module None, line 21, in tab_status_delete_versions
    - <FSPythonScript at  
/silva/service_views/Silva/edit/VersionedContent/ 
tab_status_delete_versions used for  
/silva/service_views/SilvaDocument/edit/VersionedContent/Document>
    - Line 21
   Module Products.Silva.adapters.version_management, line 139, in  
deleteVersions
   Module OFS.ObjectManager, line 460, in manage_delObjects
BadRequest: 0 does not exist