Mass Update for sales order item level Unit of measure

Hi All,

In sales order item level unit of measure wrongly assigned to other unit of measure.now we need to set it back to correct one.

In sales order ---->item level_------>Condition tab---->unit of measure need to changed is there any mass update method for this.

For ex--

Sales order  item     oldUoM   new UoM

1234             10         KG           LT

Please let me know the step to mass upload.

Thanks,

Preddy