I believe the code should be:
<select class="formMenufield_Medium" name="unit" id="unit" tabindex="4" onBlur="hideServerError('unit_ServerError');">
<option value="" <?php if (!(strcmp("", (isset($_GET["invalid"])?ValidatedField("HandlerInsert","unit"):"")))) {echo "selected=\"selected\"";} ?>>Please Select a Unit</option>
<option value="<?php echo $row_WADADynListunits['unit_id']?>" <?php if (!(strcmp("". echo $row_WADADynListunits['unit_id']."", (isset($_GET["invalid"])?ValidatedField("HandlerInsert","unit"):"")))) {echo "selected=\"selected\"";} ?>><?php echo $row_WADADynListunits['unit_name']?></option>
</select>