In any version of Mac OS X Server 10.2 or later, FTP service uses an influence listing mechanism designed to ensure that served files are usable. It presents slightly modified file names to identify files of certain types. The user sees a modified file name, but neither the file nor its actual name on the server is changed.
A "file_one" that has a resource fork, for example, would be presented as "file_one.bin", mapping that file to the MacBinary format. If the user requests file_one.bin, the server attempts to convert the file to Macbinary on the fly, thereby preserving the resource fork. If the user requests file_one without specifying the .bin extension, the server will provide file_one without its resource fork, potentially rendering the file unusable.
This mechanism also increases the likelihood of maintaining the integrity of served Mac OS X applications and Mac OS 9-bundled applications by presenting them as disk images, with the .dmg filename extension.
The influence listing mechanism can be turned off by editing the FTP configuration file /Library/FTPServer/Configuration/ftpaccess to add this line to the end of the file:
influence_listings no
For help doing this, see technical document 106619, "
Mac OS X Server: How to Locate and Edit Configuration Files".
Important: Be sure to quit the Server Settings application before modifying the ftpaccess file. If Server Settings is open while you modify the file, it will subsequently change the file back to its previous (undesired) state using data from its cache.