The last beta timed out last night and therefore stopped working in the mid of the nightly capture.
I updated to the newest beta but the scheduler always crashes with what looks like a null pointer dereferencing - here is the crash log:

Process: QRecallScheduler [45864]
Path: /Library/Application Support/QRecall/QRecallScheduler
Identifier: QRecallScheduler
Version: ??? (???)
Code Type: X86-64 (Native)
Parent Process: launchd [64]

Date/Time: 2010-09-28 13:18:16.396 +0200
OS Version: Mac OS X 10.6.4 (10F569)
Report Version: 6

Exception Type: EXC_BAD_ACCESS (SIGSEGV)
Exception Codes: KERN_INVALID_ADDRESS at 0x0000000000000000
Crashed Thread: 0 Dispatch queue: com.apple.main-thread

Thread 0 Crashed: Dispatch queue: com.apple.main-thread
0 QRecallScheduler 0x000000010003122e 0x100000000 + 201262
1 QRecallScheduler 0x0000000100028aad 0x100000000 + 166573
2 QRecallScheduler 0x0000000100006c63 0x100000000 + 27747
3 com.apple.Foundation 0x00007fff81e88a2d __NSFireTimer + 114
4 com.apple.CoreFoundation 0x00007fff80c6c678 __CFRunLoopRun + 6488
5 com.apple.CoreFoundation 0x00007fff80c6a84f CFRunLoopRunSpecific + 575
6 com.apple.Foundation 0x00007fff81e6da18 -[NSRunLoop(NSRunLoop) runMode:beforeDate:] + 270
7 QRecallScheduler 0x0000000100006141 0x100000000 + 24897
8 QRecallScheduler 0x000000010000967e 0x100000000 + 38526
9 QRecallScheduler 0x0000000100001f44 0x100000000 + 8004

Thread 1: Dispatch queue: com.apple.libdispatch-manager
0 libSystem.B.dylib 0x00007fff859e108a kevent + 10
1 libSystem.B.dylib 0x00007fff859e2f5d _dispatch_mgr_invoke + 154
2 libSystem.B.dylib 0x00007fff859e2c34 _dispatch_queue_invoke + 185
3 libSystem.B.dylib 0x00007fff859e275e _dispatch_worker_thread2 + 252
4 libSystem.B.dylib 0x00007fff859e2088 _pthread_wqthread + 353
5 libSystem.B.dylib 0x00007fff859e1f25 start_wqthread + 13

Thread 2:
0 libSystem.B.dylib 0x00007fff859e1eaa __workq_kernreturn + 10
1 libSystem.B.dylib 0x00007fff859e22bc _pthread_wqthread + 917
2 libSystem.B.dylib 0x00007fff859e1f25 start_wqthread + 13

Thread 0 crashed with X86 Thread State (64-bit):
rax: 0x0000000000000000 rbx: 0x0000000100440f00 rcx: 0x00007fffffe00080 rdx: 0x0000000000000000
rdi: 0x0000000000000002 rsi: 0x0000000000000001 rbp: 0x00007fff5fbff000 rsp: 0x00007fff5fbfefc0
r8: 0x00000001000bf078 r9: 0x0000000000000000 r10: 0x00007fff5fbfef08 r11: 0x0000000020000037
r12: 0x0000000100110c60 r13: 0x0000000100441030 r14: 0x0000000100110320 r15: 0x000000010042d2e0
rip: 0x000000010003122e rfl: 0x0000000000010246 cr2: 0x0000000000000000

Jochen,

Thanks for the bug report. It's a problem with the new scheduler code that tries to determine if two archives share the same physical device (i.e. a single hard drive or a RAID), instead of simply testing if two archives are stored on the same logical volume.

The scheduler didn't check for the possibility of a logical volume that doesn't have a BSD/IOKit device name associated with it. I don't know under what circumstances that would be true, but it obviously is for you.

And it was great timing, too! I was just hours away from releasing a new beta. I've make the fix to the scheduler and rolled it into the new beta. Expect to see an automatic update available later today.

For future reference, you can also send a diagnostic report (Help > Send Report...). The report will include any recent QRecall crash logs along with other OS and hardware configuration information that can make debugging these kinds of problems simpler.