The term Remote Volume Manager appears to be used in involved networked type systems. This is a bare bones home computer not requiring private volumes to be managed remotely by pending operations, whatever that means...

What is org.gtk?

This issue was already reported in June 2009 by ThirdBias and was written off as a bug in the kernel at the time:
http://ubuntuforums.org/showthread.php?t=1175638


Several kernels later, I am experiencing the same problem under Lucid when unmounting a USB stick off-line. As I do not believe this to be a kernel issue, I am inviting comments from the experts. Thanks!