InvalidCastException on

I have tested the smartFox example on joining Buddy’s room and got an “InvalidCastException”, anybody has any ideas what I did wrong?

if(GUI.Button(new Rect(200,260,90,20),“Enter Friend’s room”))
{
try{
Buddy buddy = smartFox.GetBuddyByName(QJ_username);
print("Buddy id: " +buddy.GetId());
print("Buddy name: "+buddy.GetName());
print("Buddy toString: "+buddy.ToString());
smartFox.GetBuddyRoom(buddy);
}catch(Exception e){
print(e);
}
}

void OnBuddyRoom(ArrayList idList)
{
print("Room name or ID: "+idList[0]);
smartFox.JoinRoom(idList[0]);
}

I got the exception when running smartFox.GetBuddyRoom(buddy).

It gets problem when you are trying to run

print("Buddy toString: "+buddy.ToString());
smartFox.GetBuddyRoom(buddy);

possibly caused by conversion from a Single or a Double to a Decimal, the source value is infinity, Not-a-Number (NaN), or too large to be represented as the destination typ

Because I don’t know how to debug in Unity, I used lots of “print” to help with the debug. The value for the specific buddy I tested are:

buddyID is 16,
buddyName is “Frank”
all other buddy properties are empty or default value.

So I really don’t understand why there is this cast problem. If you look at the Buddy class in SmartFox document, it is really simple and has no double or float data types in it. What else can cause this problem?