If you're seeing the "data disconnected" message it probably means that your server is returning bad data, probably a big fat error message.There are ways to debug your php script using log messages, error control handlers, php debuggers (like zend's debugger), etc. I would at a minimum configure an error handler to keep some kind of log or else you'll remain totally in the dark about the "data disconnected" message.
Anyway, from your description of the problem it sounds like your db might not like the data it's receiving. You are using real_escape_string() before inserting data, right?
If you use remoteobjects with your data services could just send the object and store as bytedata saves on conversion upload/download etc...
Thanks for the replies Mewk and David. This solution was to simple - I was not using mysql_real_escape_string() for this php function; I assumed I was so I was looking elsewhere.