Email response timeout

Hi all,
i need a little help...i think it's simple..

- I' ve a scripted object A that sends an email to another object B.
- The other object B receives the email and sends a response to A.

How to make this:
- If A doesn't receive the response will make a thing.
- If A receives the response will make another thing.

I think the best thing is to make a timeout event on A on receiving the response(for example 1-2 min)...can you suggest me how to code this timeout event?

Thanks in advance.

default
{
    state_entry()
    {
        llSetTimerEvent(30);
    }

    timer()
    {
        llEmail((string)recipient,subject,message);
        state waitcheck;
    }
    
}

state waitcheck

{
    state_entry()
    {
        llSetTimerEvent(30);
    }
        timer()
    {
               llGetNextEmail("", "responseOK");               
    }

    email(string time, string address, string subj, string message, integer num_left)
    {
        message = llDeleteSubString(message, 0, llSubStringIndex(message, "\n\n") + 1);

        if (subj == "responseOK")
        {   
            llOwnerSay("Response OK");
            state default;
        }
    }
    
}