The 30-year-old has not played for his country in two years following an injury-plagued spell at Real Madrid.
"I admit it was a surprise, this call. I followed the disclosure of the list for TV, mainly because I'd been told that my name might be one of those listed," he told globoesporte.com.
"When the list was published, I was extremely happy. It was like my first call-up."
Kaka won the World Cup with Brazil in 2002 and has scored 27 goals in 82 appearances for his country.