Calling a function from a hyperlink

I there, I am using fnRowCallback function to draw a hyperlink as follows:

"fnRowCallback": function(nRow, aoData, iDisplayIndex, iDisplayIndexFull) {
$('td:eq(0)', nRow).html('<ahref="javascript:void(0);" onclick='ViewMessages('+aoData[12]+');">Click</a>
}

This displays the hyperlink fine, but when i click on it, it throws an error in firebug : ReferenceError ViewMessage(test2);

Test2 is the vlaue of the record i'm trying to send into the function?

Why is this happening?

I am using ASP.NET with server side processing