Cannot pass large mail attachment with smtproutes control.

[fai0]

Hi all, i've install the Mail Toaster in a  FreeBSD 5.1 box recently, everything work fine.(And the toaster is hosting for 3 domains, 2 hold on the toaster and one is on another server, toaster is acting a mail relay for that domain)

Mail routing is like this.
toaster ip 192.168.1.1
mail server B ip 192.168.1.2
domain hold on toaster a.com , b.net
domain hold on another mail server B, c.org
mail to a.com and b.net
Internet > toaster
mail to c.org
internet > toaster > mail server B
syntax in smtproutes in /var/qmail/control
c.org:192.168.1.2

But when i send some mail with large attachment (over 1MB) the mail stop after scanning by the qmail-scanner.pl and i can show the mail by command qmail-qstat and qmail-qread ( of course qqtool.pl )
i am sure that mail server B can receive mail with attachment over 1MB ( the limit is 10MB, because before the toaster running , mail server B is connected to internet directly and it can receive mail over under 10MB.)

More, mail over 1MB can receive by the toaster.
i think that should be some mis-configure of qmail.
does anyone have idea on this problems?

Thanks very much~
=)

Fai

[fai0]

I found the problems is because the firewall installed on mail server B drop the packet send from the toaster to it.
after some fine tuning, everything work again.
Thanks for everyone attention~