It doesn't work, but at least now it hangs at:

R600_DEBUG=cs bfgminer --scrypt -o stratum+tcp://stratum2.wemineltc.com:3334 -u
user.1 -p password -I 13 -v1

 [2013-09-17 21:03:59] Started bfgminer 3.2.0
 [2013-09-17 21:03:59] Started bfgminer 3.2.0
 [2013-09-17 21:03:59] Probing for an alive pool
 [2013-09-17 21:04:00] Network difficulty changed to 1.03k ( 7.39Gh/s)
 [2013-09-17 21:04:00] Stratum from pool 0 detected new block
 [2013-09-17 21:04:00] Pool 0 is hiding block contents from us
 [2013-09-17 21:04:24] Killing OCL 0Errore di segmentazione

and as soon as I press CTRL+C I get a segfault in dmesg:
[ 1275.112334] bfgminer[6407]: segfault at 2d0 ip 00007f6a3d18ef01 sp
00007fffc765cc10 error 4 in libpthread-2.15.so[7f6a3d185000+17000]

I don't know where to find the output of R600_DEBUG=cs, sorry.