GParted wont resize extended partitions

I have dual booted windows 7 and Ubuntu 12.04 LTS and have decided that I need more space on my Ubuntu partition. I used gparted on a Live CD to shrink my Windows 7 partition (/dev/sda3) but when i try to resize the extended partition (/dev/sda4), which houses my linux partition (/dev/sda6), the right click options are greyed out and there is a key next to the extended partition.

I have resized the partitions within the extended partition before to provide room, but now I can go no further with that, and need to grow the extended partition. The free space lies to the left of the extended partition and there is a small amount of free space directly to the right as well.

Also, within the extended partition is /dev/sda5 (ntfs) , which I have no idea what is on it, but most of the space (3.42GB) is used, /dev/sda6 (ext4, mount point: /), my partition containing Linux, and /dev/sda7 (linux-swap). I hope you guys can help me with this because I really don't want to screw something up while trying to resize the extended partition.

It is likely that the extended partition is locked because your LiveCD environment is swapping to the swap partition which is inside of the extended partition.

Right-click on the swap partition and select "Swap off"