no no no.
flash sms is nothing to do with flash or .swf
flash sms is a sms, which is displayed completely and directly on ur screen, rather that going in inbox or threads. then when u hit the back key, it gets deleted automatically. u won't find it in inbox or threads. some older phones shown receiving flash sms in their logs, but most of the phones, cannot.
thus, flash sms is not traceable once deleted.