on the confirm page, there is a hidden element that passes the name to paypal, it will look like this:
<input type="hidden" name="item_name_<?php echo $eCart1_Index+1; ?>" id="item_name_<?php echo $eCart1_Index+1; ?>" value="<?php echo $eCart1->DisplayInfo("Name") ?>" />
edit that to concatenate the description:
<input type="hidden" name="item_name_<?php echo $eCart1_Index+1; ?>" id="item_name_<?php echo $eCart1_Index+1; ?>" value="<?php echo $eCart1->DisplayInfo("Name") ?> <?php echo $eCart1->DisplayInfo("Description") ?>" />