I usually can use my UDF formatted CD-RWs/DVD-RAMs as floppies (no need to use a burning software but nautilus or a terminal) by mounting them "read & write" or editing /etc/fstab for this to be done automaticaly, as explained in
a previous thread.
I've been given a DVD-RAM whose type is "UDF/ISO9660 Bridge", according to nero (I installed it because K3B refuses DVD-RAMs). I can't mount it using "mount -rw -t udf /dev/hdc /media/cdrecorder1" : "type de sys. de fichiers erroné, option erronée, super bloc erroné sur /dev/hdc, ou trop de systèmes de fichiers montés" (French for bad filesystem). Obviously, the DVD-RAM will mount with "mount -t iso9660 /dev/hdc /media/cdrecorder1" but then it will be impossible to do "packet writing" or to add a session to it.