There is a rope to tie people up.
However, one has to distinct between the reasons for ingame punishments.
If a player gets "RP-Punished", means his "crime" was done in full roleplay and the player "agreed" that his character goes to prison, then there is no need for a "technical" prison. A "chain" can also be roleplayed by such a person.
But those players are usually not causing problems that require a "coded" jail-soution.
The other case are players who (ab)use the engine for what then, ingame, gets defined as "crime", but is done in a way that annoys other players. That happens usually because some players seem to be convinced that their char does never "lose", and they will even use unfair methods / system weaknesses (for example: returning from cross, using building shadows for sniper attacks, logging, attacking a place when it's players are offline, etc.), and then declare their actions as "rping a criminal". Their behaviour can be hard on the border of violating server rules, annoyig to others, but not quite over the line.
For such players, a hard-coded jail function DOES make sense.
However, to keep an eye on such things, it would require active GMs / seers, or very responsible players - which will most likely only happen after the vbu.