Sony Worldwide Studios president Shuhei Yoshida has said the company's engineers are "working hard" on PSone support for Vita.
"Pls be patient," he added in a Twitter post earlier this week.
Yoshida made the comment just a few days before PSone title Buzz Lightyear of Star Command was spotted on the Vita PlayStation Store priced at £3.99.
NeoGAF users who downloaded it reported getting an error code when trying to play it, and a file corrupt screen when trying to view the manual.
Which PSone games would you most like to play on Vita? We revisited 25 PSone classics lat year.