performance issue in 3.7 application & SQL 2000 DB

Dear friends,

Our client is facing a performance issue. Our application comes to a deadlock situation when the number of live user are more than 45(but the licensed number of users are 86).

we are trying to solve this issue , performance by altering some customized coding. In all our customization we have locked the table using the following coding pattern,

<record variable>.LOCKTABLE;
<set the filter if required using SETRANGE/SETFILTER>
<performed the insertion, or deletion using INSERT/DELETE,DELETEALL>
COMMIT;

can any one suggest if our application performance will improve if we change our lock table pattern as below using the SLEEP command.
<record variable>.LOCKTABLE;SLEEP(2000); //Allowing the table or record variable to SLEEP for about 2000 milli seconds
<set the filter if required using SETRANGE/SETFILTER>
<performed the insertion, or deletion using INSERT/DELETE,DELETEALL>
COMMIT;

can any one suggest us will the usage of SLEEP command while locking the table will release the lock of a particular table in the defined time and relieve the application from dead lock situation.

Thanks in advance,

Regards,
B.Durgalakshmi