colon file in server repository structure

[Jan Kopidol]

Hi,

I found strange file on directory structure of my repository on server:  
"/svn/my_repository/db/revs/0/:". It has zero size and its name is ":" 
(without quotes) - colon. Does anyone know meaning of this file? I have 
several repositories, but this is only "colon file" I found. Problem is 
that I backup this part of Linux filesystem on WinXP drive via rsync and 
this file cannot be created on NTFS filesystem :D (or may be it can, bud 
i dont wanna do it - it seems wrong :D). I would like to know if i can 
safely delete this file (it seems that there are no useful data in it). 
I know i shouldnt directly manipulate with repository files on server, 
but I have strange feeling that this file shouldnt be there :D. Or maybe 
it can be fixed via some repository tool.

Thank you,

John