Well thats stupid advice John. If the debt is already past SOL (Statute of Limitations) sending them even a penny will reset it. Now you just allowed them to legally bring you to court. On the other hand, once you have a delinquent account on your credit report paying it isn't going to boost your credit score UNLESS they agree in writing to either remove the trade line or change to "Paid As Agreed." Anything other than that will do no good, but time will.
If you really find that you want to pay, pay the ORIGINAL CREDITOR. I'm sure they'd be happy to take your money, but i wouldn't hold my breath on having anything cleared up with the Debt Collector, they'll still continue to collect and you'll end up paying twice!
The bottom feeding debt collector purchased the debt for pennies on the dollar. Seriously, these guys will purchase debt for 5 cents on the dollar. Do the math. Why assist in making these guys rich when they never provided you anything!
The best advice: DON'T PAY DEBT COLLECTORS/ATTORNEYS!!!