求助，报错PHP Strict Standards

试了好多方法，没用，请问这个怎么解决，用的iis7+php5.3的，报错PHP Strict Standards: Non-static method FastJSON::convert() should not be called statically，
代码是：return FastJSON::convert($array); 就是这行出错

http://blog.csdn.net/tgh1981/article/details/7033815