every filetransfer from my XP SR1 to my Zaurus (Linux) with 3.7.1 ends with Network error. The size of the copied file or the used protocol doesn't matter, only the first block is transfered (12 kB).
Any other function is ok - delete, create directories etc.
A simultaneous SSH-Session with Putty runs without any problems. Ping with 1024 kB - no problem.