MTA mail relay issue

[Nikolaos_Liakop]

Hello ,

We have currently setup our R80.10 Cluster as an MTA which relays smtp traffic towards our internal Exchange Server.
Therefore the first MX record points to the MTA cluster, whilst the second MX record points to another SMTP Server which is off-site.
What we have faced is the following problem.
When our internal Exchange server is down for maintenance reasons, the Checkpoint MTA keeps receiving mails and attempts to forward them
on the internal Exchange, but hopelessly since the Exchange is down.
What we want is the Checkpoint MTA to forward the mail on our second MX record relay which is an off-site SMTP server.
Is this feasible ?

I know that there is a related SK (sk110369) with regard to this one, but I cannot comprehend exactly how this would solve my problem.

Thank you.