Problems mounting/dismounting drives

[mconnally]

I'm running SuperDuper! 2.6.2 and since upgrading my Mac Pro to
Snow Leopard (10.6.2) I have been having problems with unreliable
mounting of partitions used for SuperDuper! backups on Firewire
attached drives. Other Firewire drives (not used by SuperDuper!)
mount and dismount without any problem. But partitions used for
SuperDuper! backups sometimes do not appear in the Finder when
mounted. They do appear mounted to the command line df command.
If I bring up Disk Utility, then they suddenly do appear in the Finder.

Two other anomalies are seen associated with SuperDuper! backup
partitions. When unmounting the partition, these kind of entries
are always seen in the system log:
21/01/2010 14:33:13 com.apple.notifyd[13] EV_DELETE failed for file watcher 43
21/01/2010 14:33:13 com.apple.notifyd[13] EV_DELETE failed for file watcher 39
21/01/2010 14:33:13 com.apple.notifyd[13] EV_DELETE failed for file watcher 38
21/01/2010 14:33:13 com.apple.notifyd[13] EV_DELETE failed for file watcher 37
21/01/2010 14:33:13 com.apple.notifyd[13] EV_DELETE failed for file watcher 36
21/01/2010 14:33:13 com.apple.notifyd[13] EV_DELETE failed for file watcher 34
21/01/2010 14:33:13 com.apple.notifyd[13] EV_DELETE failed for file watcher 42
21/01/2010 14:33:13 com.apple.notifyd[13] EV_DELETE failed for file watcher 35
21/01/2010 14:33:13 com.apple.notifyd[13] EV_DELETE failed for file watcher 41
21/01/2010 14:33:14 mdworker[1824] CFPropertyListCreateFromXMLData(): Old-style plist parser: missing semicolon in dictionary.

And sometimes, when dismounting those partitions, the Finder crashes
with these entries in the log:
21/01/2010 14:33:17 com.apple.launchd.peruser.501[165] (com.apple.Finder[175]) Job appears to have crashed: Segmentation fault
21/01/2010 14:33:18 ReportCrash[1827] Saved crash report for Finder[175] version 10.6.2 (10.6.2) to /Users/mike/Library/Logs/DiagnosticReports/Finder_2010-01-21-143318_Shackleton.crash

Please tell me if you are aware of this problem and working on a
solution. I would be happy to help with further diagnostics if
needed.

[dnanian]

I've already replied to your emailed support request, but to repeat:

Since we have no actual interaction with hardware, Mike, and simply copy files from one location to another, I can't see how we could have any effect on volume mounting.

However, Snow Leopard is reported to have FireWire problems with some drives, and perhaps problems with some 3rd party kexts and extensions... I haven't had problems myself, but I have seen discussions on Apple's discussion forums about this kind of thing...