Writing more than 2^15 causes Exception, more than 2^21 bytes of data at once causes hang

If I try to write 32768 bytes of data or once or more, I get the follow error:

net.schmizz.sshj.sftp.SFTPException: EOF while reading packet

    at net.schmizz.sshj.sftp.PacketReader.readIntoBuffer(PacketReader.java:52)

    at net.schmizz.sshj.sftp.PacketReader.getPacketLength(PacketReader.java:57)

    at net.schmizz.sshj.sftp.PacketReader.readPacket(PacketReader.java:73)

    at net.schmizz.sshj.sftp.PacketReader.run(PacketReader.java:85)

    Suppressed: net.schmizz.sshj.connection.ConnectionException: Stream closed

        at net.schmizz.sshj.connection.channel.ChannelOutputStream.checkClose(ChannelOutputStream.java:178)

        at net.schmizz.sshj.connection.channel.ChannelOutputStream.write(ChannelOutputStream.java:159)

        at net.schmizz.sshj.connection.channel.ChannelOutputStream.write(ChannelOutputStream.java:153)

        at net.schmizz.sshj.sftp.SFTPEngine.transmit(SFTPEngine.java:269)

        at net.schmizz.sshj.sftp.SFTPEngine.request(SFTPEngine.java:124)

        at net.schmizz.sshj.sftp.RemoteResource.close(RemoteResource.java:53)

                ...

If I try to write more than 2^21 bytes at once, in SFTP.transmit(), remoteWindowSize becomes 0, causing it to call win.awaitExpansion(), which hangs forever right now as I don't think it ever sends a request to increase the window size.

Tested with 0.9.0 against OpenSSH