WF's and T's on R/3 47 Enterprise

[Marek Dziewulski]

Hi all,
 
We are currently running 45b and most of our workflows are WF and using
T (tasks). Next year we are planning to upgrade our system to 4.7
Enterprise. Do we have to rebuild or copy our workflows into WS and TS?=20
If you have any experience or knowledge in this field I would be really
grateful for sharing it with me.
 
Regards,
 
Marek