I haven't been able to reproduce this but I was copying a rather large file (218,890,240) from the Amiga to the SMB file server. Workbench hung (and hard drive activity LED stopped) -- I left it there for quite sometime (over 1/2 hr) and nothing changed. I then did a control-c in the shell window where I started smbfs, and then I got the attached hit.
I haven't been able to reproduce this one. I tried multiple times to copy same large file and did not get a hang in workbench or a hit.