There seems to be some limitation when sending data over SSL. It is stated that the maximum length of the packet size should be 1024 bytes. Is this right?

Yes, This is a limitation due to memory and not a problem in the source code. In-fact it depends on the size of heap available at any given point in time. SSL needs continuous memory chunks of (2 * ssl data size )to process the SSL requests. We have seen that over a period of time, the memory gets fragmented because of which memory allocation fails which results in SSL failure . So what we would suggest is to send 1KB or less than 1kb chunks of data.