USB 1.1 memory stick mass storage device problem

Version:    5.2-CURRENT FreeBSD 5.2-CURRENT #1: Tue Mar 30 10:50
Platforms:  Dell Dimension USB 1.1 system
            (Same problem seen on other versions/platforms.)
Device:     Sony Microvault 128MB

For some reason, with a USB 1.1 memory stick (with a FAT16 FS)
in a USB 1.1 computer, if I boot the system with the memory stick 
inserted, I can mount it.  But, if I remove it, I can't re-insert 
it and remount it.  If I insert after rebooting, I can't mount it.  
Others have reported similar problems on other platforms.
Is this a known problem or operator error?  (Is there a need 
to configure something somewhere?)

(Obviously I can paste kernel config and boot info etc., but,
I only plan to waste your time if the opinion is that USB 1.1 
mass storage devices work fine.)

-Hugh

==============================================================================
 Hugh LaMaster, M/S 233-21,    Email: lamaster_at_nas.nasa.gov
 NASA Ames Research Center     Or:    lamaster_at_nren.nasa.gov
 Moffett Field, CA 94035-1000  Or:    lamaster_at_kinkajou.arc.nasa.gov
 Phone: 650/604-1056           Disc:  Unofficial, personal *opinion*.
==============================================================================