rsync problem

[Pol Hallen]

Hi folks :-)

I've a rsync server on debian stable, many linux clients with rsync 
client runs perfectly (no errors)-never.

On osx with rsync (with same rsync options) I've this error:

failed verification -- update discarded (will try again)

same files every time.. (I also checked md5sum of these files: source 
and destination, no problem)

is a osx filesystem problem?

I also used: -avr options

what is the problem?

thanks!

Pol