Debug BSP for only one user

How do you add a debug breakpoint inside a BSP for only one or two users? AND when a breakpoint does occur, how can I tell which userid was actually stopped?

Consider this situation. My BSP application is live for many users. It has a bug, and I want to debug it using the ABAP debugger. I want to set a breakpoint in the code on the live server such that the breakpoint only occurs when the live application is run from my userID. I don't want all users requests being halted by this breakpoint.

Creating an ABAP breakpoint command for just my userid will not work either because I don't want the code to breakpoint all the time for my id, just when (if) I need to debug the code.

Thanks in advance for any help!