And whats happen when you try to mount an bluray movie after replacing the udf module ?
The command to try this is like "mount -t udf /dev/cdrom /mnt/dvd" where /mnt/dvd can be any empty folder.
If this didnt work you can check the logfile or run "dmesg | tail" and if there is still something like "UDF-fs: minUDFReadRev=250 (max is 201)" inside it mean that your udf still didnt support udf 2.5