// JavaScript Document
function stripNonNumbers(inString) {
    outString = "";
    for (i=0; i<inString.value.length; i++) {
        for (j=0; j<=9; j++) {
            if (inString.value.charAt(i) == j) {
                outString += inString.value.charAt(i);
            }
        }
    }
    inString.value = outString;
}