That is assuming he has the M3 GEP and not the RAM only pack. If he had the correct hardware he wouldn't have an issue in using that function in the settings. Incorrectly describing his hardware as something else would be his problem now wouldn't it.
There is also a reason why the M3 team keeps the GEP, RAM and rumble seperate. You pay for it 3 times, especially if you don't know what goes where.
The M3 GEP (GBA Expanion Pack) is for GBA games and can be hacked to use as a RAM pack.
The M3 RAM pack, can only be used for 1 thing the brower only.