I remember someone saying that there was an issue with Qt Mobility and more than one account of the same type... I think was a Qt Mobility issue and not constrained to mycontacts. You can try disabling one of the accounts to see if this is indeed the issue. I would also try another application like Horizontal call or fastsms with the two accounts enabled in order to figure out if it is an issue with mycontacts or with applications that use Qt Mobility. Please let me know of the outcome.