[Xapian-discuss] What is the significance of 22 in the Debian libxapian22 packages

[Charles]

What is the significance of 22 in the Debian libxapian22 and
libxapian22-dbg packages?  According to
http://packages.debian.org/search?keywords=libxapian22 they are built
from upstream versions 1.2.3 to 1.2.12 (of xapian-core?)

The reason for asking is that we need xapian-omega (and hence
xapian-core) at 1.2.8 or later.  Previously we have built and installed
directly from source but a package would be more convenient.  So I am
studying the existing Debian packages for guidance while creating 1.2.15
packages..

Charles