We have not seen such problem before, but we also consider it to be a client-side issue. The basic usage in particular does nothing really special.
You can try replacing the upload with a simple form with file input:
<form action="/save-url" method="POST" enctype="multipart/form-data">
<input type="file" name="file" id="file" />
<input type="submit" name="submit" value="Submit" />
Does the file selection and upload succeed this way?
Join us on our journey to create the world's most complete HTML 5 UI Framework - download Kendo UI