[Samba] WinXP + Samba: Explorer locking problem

[Steve]

I've the following problem using WinXP + Samba 2.2.7:

Whenever I use the Windows Explorer and roll the mouse pointer over a file (even without pressing the button), Windows locks that file (maybe to retrieve some more info?). This lock stays there for approx. 2-5 seconds ("watch smbstatus").
When I want to move or delete the file from Windows within this time, I consequently get a "file locked" error - it's hard to move a file without touching it with the mouse :)  This makes using the Win Explorer quite annoying.

So I wonder if
- anyone else has observed this problem?
- this a WinXP or a Samba problem, or both?
- I can make WinXP not to lock the files?
- there is some config option for Samba to release locks earlier, or to cache file infos, or else?

For most settings I use default options (oplocks, l2ops, kernel ops activated). The samba server runs on Linux 2.4.21, and the shares reside on a reiserfs disk.

Any help is welcome; if additional config details are required I'll post it.