fixed schema validator when you have a field named 0 (because in PHP 0 == 'a string' returns true)
fixed schema validator when you have a field named 0 (because in PHP 0 == 'a string' returns true)

git-svn-id: 7038a89b398528086dab5106cc8d05243a854dbc@6991 ee427ae8-e902-0410-961c-c3ed070cd9f9

theodo/symfony1.1-backports,theodo/symfony1.1-backports,theodo/symfony1.1-backports