private bool SerializeString(string aString, StringBuilder builder)
        {
            // Is a GUID?
            if (PBXObject.IsGuid(aString))
            {
                builder.Append(aString);
                return(true);
            }

            // Is an empty string?
            if (string.IsNullOrEmpty(aString))
            {
                builder.Append(QUOTEDSTRING_BEGIN_TOKEN);
                builder.Append(QUOTEDSTRING_END_TOKEN);
                return(true);
            }

            builder.Append(aString);

            return(true);
        }