filereference.upload ... works on localserver but not on webserver

I'm uploading images via filereference.upload ... works fine when testing on local machine with apache. once I port everything to my web-based server ( shared server with a webhosting company ), the upload fails.

- do not get any errors such as SECURITY_ERROR , HTTP_STATUS , IO_ERROR
- do get 1 PROGRESS event - only 1 - but it already shows 100%
- do get COMPLETE event after a couple of seconds
- do not get UPLOAD_COMPLETE_DATA, but do get it on localhost
- do not get the image on the remote server

- my local php is 5.2 ... webserver php is 4.4 ...
- I have tried setting 757 as file permissions for image directory
- all php, swf, image directories are in the same domain, though in different directories.
- I have tried uploading the image to the same directory as php directory itself

any thoughts?

thanks,
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