HTTP-REST plugin - how to PUT binary content?

Hello.

Does anybody know what is the proper way to use HTTP-REST Plugin methods to upload binary content to the server using PUT method?

I have no difficulties to upload a text file (even with the size of few megabytes), but even with a small binary file (30-40 KB) server returns HTTP error 500.

Changing the value of contentType field to "application/octet-stream"  doesn't help.

Thank you.