JavaScript multidimensional array editing

Is is possible to use Array.RemoveAt or Array.splice with the newly implimented (Unity 3.2) JS multidimensional arrays? For instance, say I initialize a 2x2 array thusly:

var myArray : new int[2,2];
myArray[0,0] = 1;
myArray[0,1] = 3;
myArray[1,0] = 5;
myArray[1,1] = 2;

When I try to:

myArray.RemoveAt(0);

it returns an error: 'RemoveAt' is not a member of 'int[,]'.

I'm trying to cycle through a set of arrays, testing if the 1st, 2nd, 3rd, etc. values match an external value, and if they don't, deleting the array the unmatching value is contained in from the larger array containing the set. Application is iPhone based so efficiency is also a factor, would creating a custom class that contains an array be a drain?

Thanks!