non-numeric value encountered @ sfYamlInline.php

[xerc]

Propel/runtime/lib/parser/yaml/sfYamlInline.php

Line 130 in 3f7a284

(count($keys) > 1 && array_reduce($keys, create_function('$v,$w', 'return (integer) $v + $w;'), 0) == count($keys) * (count($keys) - 1) / 2))

return (integer) $v + (integer) $w;

[jestep]

Following, would prefer not to patch my own installations to have them overwritten on a future update.