body_timeout — network timeout once the DATA phase is complete
body_timeout = 600
The amount of time in seconds to wait for a response once the
DATA phase has been terminated by a
CRLF.CRLF. This timeout is relatively long because this is the only phase of transmission which involves significant network transmission. This option applies to outbound mail only.
The default value is
body_timeout is valid in the binding, binding_group, domain, and global scopes.