Display Warning on Setting TECO/CLSD with Outstanding Requisition/Reservati

HI ALL,

I got one requirement as below:

In PM work order when user select the system status TECO (Technically completed) or CLSD (CLosed). We need display the warning message, if there one or more open

purchase requisitions or reservations for this work order.

Please let me know whether we can achieve this by making configuartion settings (OR) by writting code in user exit.

If this done through configuartion, please let me know the path

where we can do this setting.

OR

If this can be done through user exit then any suggestions on this.

Regards

RAMU