I'm having a similar problem, and I don't know if its because i have 2 separate macros for Cure and Cure II....

This is what I'm running:
/macroicon "Cure"
/ac "Cure" <mo>
/ac "Cure" <t>
/ac "Cure" <me>

and:
/macroicon "Cure II"
/ac "Cure II" <mo>
/ac "Cure II" <t>
/ac "Cure II" <me>

Neither of them work when i mouse over anymore.