According to the AA website not all economy tickets are eligible for (full) mileage credit:

Earning AAdvantage Miles
With Cathay Pacific's participation in oneworld, AAdvantage members traveling in all classes of service earn miles.
Effective February 1, 1999,
First Class fares (booked in F or A) earn 100% mileage credit plus 50% class of service bonus.

Business Class fares (booked in C, D, I and J) earn 100% mileage credit plus 25% class of service bonus.

Eligible Economy Class fares earn 100% mileage credit:
-From February 1 to March 31,1999 eligible Economy Class fares are Y and W.
-From April 1 to June 30, 1999 eligible Economy Class fares are Y, W, B and H.
-From July 1, 1999 and on eligible Economy Class fares are Y, B and H.


[This message has been edited by mijne (edited 04-14-99).]

[This message has been edited by mijne (edited 04-14-99).]