Record from Mic-in as it were Line-In

[agarza]

I owned a T30 which included the Line-in port which served me to record Formula1 races (only the commentary) to my HDD using a program called Audacity.

It worked great, however, now that Thinkpads do not have the Line-in connector, only the Mic-in, I decided to plug it the 3.5 jack, under Windows Sound panel, I see that I cannot choose to record from dual channel (left, right).

Is there a way to record sound dual channel?