Alright, I got debug going, I see something not sure if it the cause:
trackuploads no id found in POST upload req

[code]
2010/03/04 16:38:14 [debug] 62066#0: *1394 http header: "Pragma: no-cache"
2010/03/04 16:38:14 [debug] 62066#0: *1394 http header: "Cache-Control: no-cache"
2010/03/04 16:38:14 [debug] 62066#0: *1394 http header done
2010/03/04 16:38:14 [debug] 62066#0: *1394 event timer del: 22: 1267738698166
2010/03/04 16:38:14 [debug] 62066#0: *1394 generic phase: 0
2010/03/04 16:38:14 [debug] 62066#0: *1394 test location: "/"
2010/03/04 16:38:14 [debug] 62066#0: *1394 test location: "file_upload_progress"
2010/03/04 16:38:14 [debug] 62066#0: *1394 test location: ~ "/\.ht"
2010/03/04 16:38:14 [debug] 62066#0: *1394 using configuration "/"
2010/03/04 16:38:14 [debug] 62066#0: *1394 http cl:115 max:262144000
2010/03/04 16:38:14 [debug] 62066#0: *1394 generic phase: 2
2010/03/04 16:38:14 [debug] 62066#0: *1394 upload-progress: get_tracking_id
2010/03/04 16:38:14 [debug] 62066#0: *1394 upload-progress: get_tracking_id no header found
2010/03/04 16:38:14 [debug] 62066#0: *1394 upload-progress: get_tracking_id no id found
2010/03/04 16:38:14 [debug] 62066#0: *1394 [b]trackuploads no id found in POST upload req[/b]
2010/03/04 16:38:14 [debug] 62066#0: *1394 generic phase: 3
2010/03/04 16:38:14 [debug] 62066#0: *1394 post rewrite phase: 4
2010/03/04 16:38:14 [debug] 62066#0: *1394 generic phase: 5
2010/03/04 16:38:14 [debug] 62066#0: *1394 generic phase: 6
2010/03/04 16:38:14 [debug] 62066#0: *1394 access phase: 7
2010/03/04 16:38:14 [debug] 62066#0: *1394 access phase: 8
2010/03/04 16:38:14 [debug] 62066#0: *1394 post access phase: 9
2010/03/04 16:38:14 [debug] 62066#0: *1394 upload-progress: ngx_http_uploadprogress_content_handler
2010/03/04 16:38:14 [debug] 62066#0: *1394 malloc: 0000000801159000:4096
2010/03/04 16:38:14 [debug] 62066#0: *1394 http client request body preread 115
2010/03/04 16:38:14 [debug] 62066#0: *1394 http init upstream, client timer: 0
2010/03/04 16:38:14 [debug] 62066#0: *1394 malloc: 00000008011FD000:5418
2010/03/04 16:38:14 [debug] 62066#0: *1394 http script copy: "X-Forwarded-For: "
[/code]