So I made a last login decrypter a while back.
It should work (as long as your Java paths aren't fucked up)
(Jotti never works for me unless I proxy, so I used Scan4You.net aka pay to scan)
It should be pretty obvious these are all false positives >_>
Make sure Minecraft isn't running when you use this tool.
It takes the file, replaces it with your current lastlogin, scans it, reads the output, then puts your lastlogin back.
I hope you enjoy.