I double and triple checked this and used several different ftp servers to rule out any problem. I took the line you provided "drwxrwxrwx 20 0 0 0 May 21 17:09 http" and loaded this into FlashFXP and it came out perfectly.
When "Unknown Time Zone / Use Server Time" is selected no modification to the time is made.
I'm sorry but I was unable to determine a problem with FlashFXP.
I restarted FFXP some times and it happened on other ftps, too.
But now it shows correct times, I deleted all files from FFXP dir, except sites.dat and I reset the password.
Sorry for this circumstances