When connecting to AFP shares in the new Mac OS X 10.5 (Leopard), you may get a -5002 error when the server only supports clear text passwords. To resolve, either disable clear text passwords on the server side, or change the following plist:
~/Library/Preferences/com.apple.AppleShareClient.plist
You need to change the afp_cleartext_allow value to “Yes” “true” or “1” (depending on the current values you see, either “false” or a “0”).
Here’s an excerpt from my file:
...
<key>afp_cleartext_allow</key>
<true />
<key>afp_cleartext_warn</key>
<integer>0</integer>
<key>afp_default_name</key>
<string></string>
...