[EXIM] Exim is too fast?

Hi there,
I have the problem that the ISDN-connection is _very_ slow when big mails
are transfered from one mail host to another, it's nearly impossible to
use a simple telnet then.
Is Exim the problem or the router, can I do something against?

1. Limit Exim to use less then 6,4 KB/s?
2. Configure a filter so that mails > 1 MB are routed different?

Any ideas, or hints? Is this a common problem?
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M a r k   S e u f f e r t                             captain@???
Pirates Communication                              http://www.pirate.de

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