Upload error using launchpad

Freedom

Environment:
TeamSite 6.5, SP1
Solaris 8

User is working in a shared workarea and the user has a permision to modify one file (775, the user has group permission) in one directory (775 for directory, but the user is not in the group). The user can use Launchpad to edit the file, but when the user uploads the file, following error occurs:
"Error Uploading file: C:\IWTemp\..... " to TeamSite Server. Operation Failed please check the accesspermissions on the file.

It worked in 5.5.2 environment.

Thanks for your help.