Hi Shailendra.
I went through the SampleAttachFileToResource.java example.
And I recognized that at least in my version there is no need to do a base64 conversion to attach a file.
In my version, the TRANSFER_ENCODING is set to "binary", even though I see the code to do a base64 conversion as well, but it isn't used.
So, from this point of view, soap-ui should be able to send the file just as a normal multipart http request, using the normal attachment functionality of soap-ui.
But to be honest, I haven't tried that yet.
Regards
...........Michael