Turn multidimensional array into string and then back?

[hooligan2001]

Hey guys/gals

I have a multidimensional array like the following that i need to turn into a comma delimited string to save in a mysql database.

userItems = [[0,2],[22,4],[32,2],[28,4],[88,2],[76,4],[13,9],[17,45]]; 

Now thats not a problem, i use this function.

function JoinUserItems() {
    sendItems = userItems.join(",");
    trace(sendItems);
} 

Now when i use that function it turn my multidimensional array into this string
for me to save to mysql.

0,2,22,4,32,2,28,4,88,2,76,4,13,9,17,45 

Now the problem is how do i change it back to its original form as a multidimensional array.
I tried this,

function SplitUserItems() {
    t = sendItems.split(",");
    trace(t);
    for(i=0; i< t.length; i++) {
        if(i%2) {
            trace("odd");
        }else{
            recieveItems.push(t[i],t[i+1]);
            trace("even");
        }
    }
    trace(recieveItems);
} 

But im pretty sure it only make it a one dimensional array. But its crucial i have it as a multidimensional array.

Any thoughts?

Thanks in AdvancE