Retrying a request on other servers

[jeff saremi]

Is this a feature of HaProxy? and if so what is the corresponding option to 
enable it.
Basically, i want Harpoxy to resend the request which as already received a 503 
from one server, to another server in the same backend.
And i'd like to control how many tries to do.
I looked at that options: "retries" and "redispatch" but they don't seem to be 
doing this.
thanksJeff