Mine

# enable uploads
$EnableUpload = 1;
# Allow previous versions of uploads to be kept
$EnableUploadVersions=0;
# allow users with edit rights to upload
$HandleAuth['upload'] = 'edit';
# Path to uploads directory
$UploadDir = "/usr/share/horde3/pmwiki/uploads"; 
# URL to uploads directory                                              
$UploadUrlFmt = "https://wiki.wrl.org/horde3/pmwiki/uploads";
# Prefix uploads with group and user name
$UploadPrefixFmt = '/$Group/$Name';
# Maximum file size for uploaded files
$UploadMaxSize = 10240000;