I was talking about the versionBits from Rusty's email (pasted below) and
simplifying that by XT adopting the patch as Gavin had seemed agreeable to.

Adam

Rusty wrote:
> Agreed.  Unfortunately, a simple "block version >= 4" check is
> insufficient, due to XT which sets version bits 001....111.
>
> Given that, I suggest using the simple test:
>
>         if (pstart->nVersion & 0x8)
>             ++nFound;
>
> Which means:
> 1) XT won't trigger it.
> 2) It won't trigger XT.
> 3) You can simply set block nVersion to 8 for now.
> 4) We can still use versionbits in parallel later.