Ok, I know you have tried this, but double check first...is anyone using that directory?
This is why you normally get the busy message when trying to unmount something.

	fuser -cu /mount_point

One thing to note, if you were in that directory and then started another shell, the old shell
may still be sitting in the directory you are trying to unmount.  Exit back to that shell and
then cd somewhere else.





To forcefully unmount a busy filessystem in Solaris 7, do the following:
	lockfs /mount_point
	fuser -kc /mount_point
	umount /mount_point


Solaris 8 has added a new option to umount to help out:
	umount -f /mount_point
	
From the man pages:
     -f    Forcibly unmount a file system.

           Without this option, umount does not allow a file sys-
           tem  to  be  unmounted if a file on the file system is
           busy. Using this option can cause data loss  for  open
           files; programs which access files after the file sys-
           tem has been unmounted will get an error (EIO).