Row locks in DB2/400 UDB

All

Is there a way to lock a row in DB2/400 UDB SQL without using commitment 
control?  

We have a table that holds the 'next sequence number'.  Whenever several 
processes access the table, we end up with a scenario like:

  program A accesses the table and grabs 
    the next counter number (counter number = 50)
    
  program B accesses the table and grabs 
    the next counter number (counter number = 50)
    
  program B adds one to the counter 
    number, and updates the table (counter number = 51)
    
  program A adds one to the counter 
    number, and updates the table (counter number = 51)
  
Now, there are two transactions with an identical sequence number.

We're doing a simple select to fetch the sequence number, and we are not using 
commitment control.

Any suggestions?

Thanks

-Doc