Follow the instructions here, using the patch tarball from here. Add the following entry or similar to /etc/fstab
/dev/sda3 /media/Shared hfsplus rw,exec,auto,user 0 0
This will automatically mount the filesystem as read-writable, with the option to run executables from it. All users will be able mount and unmount the partition.
IMPORTANT!!!
Make sure that you set the permissions appropriately on the root directory of the mounted filesystem. Once the filesystem is mounted e.g. with mount -a, do:
sudo chmod 775 /media/Shared
sudo chgrp disk /media/Shared
Replace /media/Shared with your mountpoint accordingly.
This gives the owner (root), and anyone in the group ‘disk’ write permission to the root of the filesystem. To add a user to the disk group:
sudo usermod -a -G disk <username>
Replacing