update:
I tried using new gpuminer implementation from ckolivas. but it's giving me a segmentation fault:
ckolivas-cpuminer-b66aa45$ ./minerd --gpu-threads 1 --url
http://pit.deepbit.net:8332/ --user myuser --pass mypassword
[2011-06-29 15:49:10] Init GPU thread 0
[2011-06-29 15:49:10] List of devices:
[2011-06-29 15:49:10] 0 GeForce 8600 GT
[2011-06-29 15:49:10] Selected 0: GeForce 8600 GT
[2011-06-29 15:49:23] Initialising kernel poclbm.cl without BFI_INT patching, 1 vectors and worksize 512
[2011-06-29 15:49:36] initCl() finished. Found GeForce 8600 GT
[2011-06-29 15:49:36] 1 gpu miner threads started
[2011-06-29 15:49:36] 0 cpu miner threads started, using SHA256 'sse2_64' algorithm.
[2011-06-29 15:49:37] Long-polling activated for http://pit.deepbit.net:8332/listenChannel
Segmentation fault
Then I tried again using ./minerd --gpu-threads 1 --url
http://pit.deepbit.net:8332/ --userpass myusername:mypassword
[2011-06-29 15:52:35] Init GPU thread 0
[2011-06-29 15:52:35] List of devices:
[2011-06-29 15:52:35] 0 GeForce 8600 GT
[2011-06-29 15:52:35] Selected 0: GeForce 8600 GT
[2011-06-29 15:52:46] Initialising kernel poclbm.cl without BFI_INT patching, 1 vectors and worksize 512
[2011-06-29 15:52:46] initCl() finished. Found GeForce 8600 GT
[2011-06-29 15:52:46] 1 gpu miner threads started
[2011-06-29 15:52:46] 0 cpu miner threads started, using SHA256 'sse2_64' algorithm.
[2011-06-29 15:52:49] Long-polling activated for http://pit.deepbit.net:8332/listenChannel
[2011-06-29 15:52:52] [630.46 | 1197.87 Mhash/s] [0 Accepted] [0 Rejected] [0 HW errors]
[2011-06-29 15:52:57] [1601.08 | 1786.52 Mhash/s] [0 Accepted] [0 Rejected] [0 HW errors]
[2011-06-29 15:53:02] [1255.39 | 1513.48 Mhash/s] [0 Accepted] [0 Rejected] [0 HW errors]
*** glibc detected *** ./minerd: malloc(): smallbin double linked list corrupted: 0x00007f20b8dbcdc0 ***
======= Backtrace: =========
/lib/x86_64-linux-gnu/libc.so.6(+0x76bb6)[0x7f20c1de6bb6]
/lib/x86_64-linux-gnu/libc.so.6(+0x79e78)[0x7f20c1de9e78]
/lib/x86_64-linux-gnu/libc.so.6(__libc_malloc+0x6e)[0x7f20c1dec31e]
/usr/lib/libcuda.so(+0x17eddf)[0x7f20becb0ddf]
/usr/lib/libcuda.so(+0x192fb1)[0x7f20becc4fb1]
/usr/lib/libcuda.so(+0x18fc8a)[0x7f20becc1c8a]
/usr/lib/libcuda.so(+0x1900fc)[0x7f20becc20fc]
./minerd[0x402e18]
/lib/x86_64-linux-gnu/libpthread.so.0(+0x6d8c)[0x7f20c230fd8c]
/lib/x86_64-linux-gnu/libc.so.6(clone+0x6d)[0x7f20c1e5604d]
...
Any hints?