Sync MySql to MS Sql database

Hi, I not sure if this maybe the most appropriate group to post to but it is kind of related. Here goes: I have a client who runs an internal Ms Sql database. They have a website which runs a php/mysql backend for storing data. They want to be able to synchronize the data between the two to keep it up to date. Does anyone know of a script/class that handles something similar to this ? Seems pointless to re-invent the wheel if its already been done. Regards Matt