Try:
Code:~a::
IfWinActive, World of Warcraft
{
ControlSend,, {a down}, ahk_id %wowid1%
ControlSend,, {a down}, ahk_id %wowid2%
Return
}
~a Up::
IfWinActive, World of Warcraft
{
ControlSend,, {a up}, ahk_id %wowid1%
ControlSend,, {a up}, ahk_id %wowid2%
Return
}