[CentOS] LVM thinpool snapshots broken in 6.5?

Hi,
I just installed a CentOS 6.5 System with the intention of using thinly 
provisioned snapshots. I created the volume group, a thinpool and then a 
logical volume. All of that works fine but when I create a snapshot 
"mysnap" then the snapshot volume gets displayed in the "lvs" output 
with the correct information but apparently no device nodes are created 
under /dev/mapper/ or /dev/(volumge_group_name).
Any ideas what might be going on here?

Regards,
   Dennis