During lunch, asking an old japanese friend what’s the bad number in japanese. He said it’s 4 because it sound like “death”. This means “四” and “死” in japanese pronouce like in 吴语. He told me another chinese from 宁波 also told him that all “one two three four” were sounding like their dialect.
Here is some search:
日语吴语和闽语: http://www.confucianism.com.cn/html/hanyu/8470050.html
http://tieba.baidu.com/f?kz=404978836