[CentOS] shrink LV with ext3 filesystem

Hi.

I want to make a snapshot from a logical volume and noticed that there 
must be enough free disk space in the volume group. Actually there is no 
   free disk space left.
How do i shrink online /var without losing any data or restore from 
backup? I do not have physical access to the server.


Specs:

Dell PE SC1430 with a 5/i RAID Controller
one RAID 1 array from the Dell RAID controller
2 partitons (boot and LVM)
1 VG
3 LV (swap, /var (/dev/VolGroup00/LogVol02) and / formatted with ext3)
/dev/mapper/VolGroup00-LogVol02 211G   39G  162G  20% /var


Thank you in advance.

Thomas Antony