Backup Kmail and sub-folders

Hi all, How to backup folders in Kmail (+ some others in ~/.kde/share) ? When i backup the kmail folder, after a restore in atnother machine, i only have the 2 first level of folders visible. The third level is created (Sub-Folder2), but all mails are not restored. Mail | Folder Sub-Folder1 Sub-Folder2 Any ideas ? Thanks. -- Banthat Sengsavanh