12.04 - Ubuntu has two kernels in /boot

my server running Ubuntu 12.04.4 LTS has two kernel images in /boot
at the moment 3.11.0-19 and 3.2.0-60
And every time i do a dist-upgrade the both get updated.
Is this necessary or how can i remove the "oldest" one?

as Nux said i've removed older kernels. now it shows:

dpkg --list | grep linux-image
linux-image-3.11.0-20-generic 3.11.0-20.34~precise1
Linux kernel image for version 3.11.0 on 64 bit x86 SMP
linux-image-3.2.0-54-generic 3.2.0-54.82
Linux kernel image for version 3.2.0 on 64 bit x86 SMP
linux-image-generic-lts-saucy 3.11.0.20.18
Generic Linux kernel image

and uname -r still says 3.2.0-54
why not 3.11.0-20 ?

You can know what version you are using :

uname -r

To remove old kernels just follow this answer :

How to remove old kernels