sort order of documents in a collaboration room

hi everybody

i have a collaboration room where documents are stored in it. the sort order of my folders in the collaboration room is determined by the names of the folders.

now there are many folders in folders and at the bottom-level-folder there are the documents stored. these documents are sorted by the names of the documents too.

now my problem:

the sorting of the folders by name is OK, but at the bottom-level in the bottom-level-folder i need the documents sorted by "modified"-date (for all users). How can i easy made this change? (hope not to make a new layout set...:-() can you please post a guidance?

thank you for your help!

flo