Trouble in Hanging up call from a specific number

Question

Hi all,

I have made a small windows mobile application for hanging up calls from a specific number. I am using Tapi to manage my call.. but somehow my comparison does not work!!! When I compare numbers, the condition simply fails! here is my code

void callAction(Call call)
    {            
        CallInformation ci = call.Info;
        String x= "+12345677844";
        String y = SystemState.PhoneIncomingCallerNumber;
        if (String.Compare(x,y)==0)
        {
            call.Hangup();
        }
    }

I also tried to get the current caller using

SystemState.PhoneIncomingCallerNumber

Even though they return the correct value, my compare statement fails.. Any idea why? Am I over looking something silly??

Thanks in advance,
Abdel Olakara