Today I was trying to use [Phing] in shared hosting server, but as you will see, Phing can't do a lot of it's functionality without direct access to server (over shh for example). [...] Things get worse, when you try to sync files in shared hosting environment, where only FTP is available. [...] Code in the hole some months ago posted solution which uses Net_FTP (FTP functionality wrapper) package to upload files to server. I decided to try given solution, so I modified it to download source code from SVN first and then upload them.
His Phing configuration sets up the application, defining the source directory, the files to push, the FTP connection to make and pushes the files over out of an svn export. He has a slightly different solution (no code/config for this one) that would grab the last revision value from the remote server and only push out the files have have changed since then.