just to add to this,
the new version of zencart works on the newer php 5.3 but struggles to work on anything before php 5.3 so no one should go upgrading their zencart quite yet
Yes this is a catch 22 situation - after upgrading to 5.3 we had to revert to an earlier PHP version so anyone upgrading may have difficulty running
I am looking at a way of mass updating all the zencart sites with the Zencart patch and then upgrading PHP to 5.3 - this should have the least impact on site, please not though for anyone hosting with us this is not anything we have control full over and as part of the service i am looking at ways to solve the issue Zen have created.
The is one of the problems of using free opensource scripts - basically you are left on your own to patch and fix to suit.
If any of our clients must have the new version I can move to a server that has been upgraded to 5.3 but tbh i dont see any panic at the moment and hopefully I can get servers fully updated without bringing sites down.