osm api 0.6 upload GPX track

Hello guys,

I quite fighting with OSM API v0.6 and upload GPX track task. I'm developing application for Android and trying to use this method. Firstly I though it should be a problem of login, so I changed login mechanism to OAuth. Anyway same result now.

After selecting track and settings all parameters (description ('test'), tags ('test'), visibility ('public')), uploading always return 400 Bad Request, no content, no error message

---------- REQUEST -----------
org.apache.http.client.methods.HttpPost@427e06f8, url: http://api.openstreetmap.org/api/0.6/gpx/create
headers: Content-Type: multipart/form-data
headers: Accept-Charset: ISO-8859-2, utf-8
headers: Accept-Encoding: gzip,deflate
headers: User-Agent: Locus/2.5.6 (Linux; U; Android; en-us)
HttpPost entity:com.google.android.common.http.MultipartEntity@427e0d98

---------- RESPONSE -----------
statusLine:HTTP/1.1 400 Bad Request
headers:Date, Thu, 16 Aug 2012 13:34:33 GMT
headers:Server, Apache/2.2.22 (Ubuntu)
headers:X-Powered-By, Phusion Passenger (mod_rails/mod_rack) 3.0.14
headers:Vary, Accept-Language,Accept-Encoding
headers:Content-Language, en
headers:Cache-Control, no-cache
headers:X-Request-Id, 0bbf0e2fd3e78e4f855718f7e53dbef5
headers:X-Runtime, 0.366059
headers:X-UA-Compatible, IE=Edge,chrome=1
headers:Status, 400
headers:Content-Encoding, gzip
headers:Content-Length, 21
headers:Connection, close
headers:Content-Type, text/html; charset=utf-8

exactly same track uploaded by web site works. Have someone any idea or any method how to test what is problem on OSM server? Thank you!