Hard to say what the problem could be.
I would double check that the files in /etc/OpenCL exists (they get extracted there when you accept the sdk license)
ls -l /etc/OpenCL/vendors/
-r--r--r-- 1 user user 15 Jan 27 04:13 amdocl32.icd
-r--r--r-- 1 user user 15 Jan 27 04:13 amdocl64.icd
if in doubt, just do another
cd /; tar xzf /opt/AMD-APP-SDK-v2.4-lnx64/icd-registration.tgz
Also on linuxcoin I had problems with the miners in /opt/miners, so I copied
my directory with the miners from my desktop to /home/user
And if you start your miners in a SCREEN session, you have to add something to .screenrc
setenv LD_LIBRARY_PATH "/opt/AMD-APP-SDK-v2.4-lnx64/lib/x86_64/:/opt/ati-stream-sdk-v2.1-lnx64/lib/x86_64/"
setenv DISPLAY ":0"
Maybe one of that helps