String in array is null when checking length, help bug?!

For some reason if a string is blank in a String array requesting it's length will shoot a null error which causes it to exit the program loop messing everything up

Example

 var AttributeNames[] : String[];
 AttributeNames = new String[39];
 Debug.Log("length is "+AttributeNames[0].length);

I've tried using Length instead of length no difference. I tried to also check to see if its blank

e.g.

 if(AttributeNames[0]!="")
 {
     Debug.Log("length is "+AttributeNames[0].length);
 }

But for some reason it bypasses that and thinks that the string is not blank. is there an alternate way to check if a string is blank without using length or !="" ?

I didn't have this problem at all until i upgraded to unity 3.3

Thanks.