Is it possible to run some programs on a dedicated connection, and common ISDN for the rest? So that browsing pages doesn't slow quotes and orders?
I assume you are talking about having two seperate connections? If so, it would be pretty simple to do with policy based routing or static routes but you would need a real router like a cisco. If it's two internet connections versus one being private like a leased line you'd probably need an ACL on there also.