PostgreSQL 64 Bit XIDs - Transaction IDs

Hello,

With a database admin of a commercial database system I've discussed
that they have to provide and they also achieve 2^31 transactions per
SECOND!
As PostgreSQL uses transaction IDs (XIDs) in the range of 2^31 they
would turn around in about one second.

How can one achieve this with PostgreSQL?
What is the status and plan of 64 Bits XIDs?

I saw that 64 Bit XIDs were already discussed in 2005 but never found
into the code:
http://postgresql.1045698.n5.nabble.com/A-couple-of-patches-for-PostgreSQL-64bit-support-td2214264.html

Thnx.

Ciao,
Gerhard