Hi, I read this post on MLPPP:
http://forum.mikrotik.com/viewtopic.php?t=2347&highlight=ppp+multilink
But I cannot tell if this was somebody trying to contribute of if it was a feature. Anyway has anybody used multilink PPP with up to four ADSL pci cards before? It’s just a supplier we can soon use has this feature and they seem to think it’s only posssible to use with a Cisco router for £2,000?
ADSL is NOT suported (Yet…) 
Not in PCI cards at this time…
Ext. ADSL works.
Ext. ADSL works.
Do you mean external ethernet or usb modems?
You can use external ethernet modems only.
No the MT does not support MLPPP. But Linux and BSD do.
Cisco is not the only way to go.
We are working on getting the MLppp up and running with the adsl whalesaler here. The big problem is that with pppoe being proxyed to us. If the proxy server does not have it setup, it wont work.
So you need to talk to the company that owns the dslams if you are going to have a chance in hell of getting it working.
You can look over this link,but they use mlpppoa
http://www.freestuffjunction.co.uk/bondedcd.shtml
I will probably get it working with linux and then use MT behind that as now. The ISP aparantly uses “Redback” routers which provide MLPPP so I will have to find out more. Thanks for the reply 
How are things going with the ADSL bonding?
Not tested it yet!
We have an ADSL service only just being made available on May 25th. When that time comes I will be able to tell you. Currntly we are using a satellite connection.