problems with directly saving indesign files to server

hello,

I got this week a power mac g5 with mac os x 10.4.7, before I had a pmac g4 with mac os x 10.3.9

our server is a windows 2003 server with services for macintosh, so we use afp and not smb to connect to our server.

my problem is, that I get very often in indesign 2.0.2 this error message:

"filexzy.indd" can not be saved under a new name. the file "filexzy.indd" is corrupt
(or something like that, I translated it from the german version)

at this point I can't even save to the local harddisk, I only can close the document without saving.
also indesign crashes sometimes during saving a document.

I work this way:
I directly open files from our fileserver (15 to 50mb indesign files), than I "save as" approximately every hour my work to a new file, so it's easier for me to go back to an older version.

the above mentioned error message I also got with my old pmac g4 and mac os x 10.3.9 two or three times a day, now with mac os x 10.4.7 and pmac g5 I get it almost at every "save as"-command!

so I would like to ask you, if there are known problems between macos x 10.4.7/indesign 2.0.2/windows 2003 server

yes, I should use indesign cs 2 4.0.4, but
- every other colleague still use indesign 2.0.2
- cs 2 has also this problem, but not that often as indesign 2.0.2

thanks for your help in advance!

regards,

ferdinand