i do not think my old 6310i and T39M are A2DP compliant...
BT profiles are dependent to the hardware, if the hardware does not support it there is no point of putting a BT profile there, besides that, that particular profile will not work at all if it is not supported... in addition, A2DP & AVRCP were only added starting from BT V. 1.2...
in the case of S60, A2DP and AVRCP are now fully supported across the product range of all S60 3rd FP1, hence all the products with FP1 are ready for A2DP, AVRCP among others, (although N91 8GB is an exception, but this too was approved for A2DP) but it is up to Nokia or operators to decide if all the profiles will be made available or cripple some coz of so called marketing positioning and strategy...