The Failed/Retry logic is broken

[lupin]

Client:Flashfxp 2.2 build 994
Server:Proftpd 1.2.9

errors:
================================================== ================
227 Entering Passive Mode (1??,??,??,???,5,193)
RETR rzr-s2.003
Negotiating SSL/TLS session...
550 too many downloading threads under this server , try later.
Transfer Failed!
PASV
227 Entering Passive Mode (1??,??,??,???,5,194)
RETR rzr-s2.005
================================================== =================

When the client got "too many downloading threads under this server " error,it will mark the file as failed,but in fact the real reason is
the server is "busy".
It should be treated as the "busy" status which is something like when connecting to a busy server and retrying under the user's seting.

Because if the server marks the files as "failed" when server is "busy",the user has to "unmark" the files manually very often to let flashfxp transfer again and again!!!!

Flashfxp is great,thanks very much!