Won't build on Debian stable. ./configure says “intltool too old” despite newer version being available.

Tried compiling from the tarballs for 1.15.7, 1.15.5 and 1.14.6 on a fully updated Debian stable (12.7). All failed with the “intltool too old” message wanting a version >= 0.40.4 despite version 0.51.0-6 being installed.

checking for intltool >= 0.40.4...  found
configure: error: Your intltool is too old.  You need intltool 0.40.4 or later.
ed@alice:~/temp/liferea/liferea-1.14.6$ cat /etc/deb
debconf.conf    debian_version  
ed@alice:~/temp/liferea/liferea-1.14.6$ cat /etc/debian_version 
12.7
ed@alice:~/temp/liferea/liferea-1.14.6$ uname -a
Linux alice 6.1.0-25-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.1.106-3 (2024-08-26) x86_64 GNU/Linux
ed@alice:~/temp/liferea/liferea-1.14.6$ apt show intltool
Package: intltool
Version: 0.51.0-6
Priority: optional
Section: devel
Maintainer: Debian GNOME Maintainers <pkg-gnome-maintainers@lists.alioth.debian.org>
Installed-Size: 182 kB
Provides: xml-i18n-tools
Depends: gettext (>= 0.10.36-1), patch, automake | automaken, perl:any, perl (>= 5.8.1), libxml-parser-perl, file
Homepage: https://launchpad.net/intltool
Tag: devel::i18n, implemented-in::perl, interface::commandline,
 role::program, scope::utility, use::converting, works-with-format::xml
Download-Size: 50.8 kB
APT-Sources: http://deb.debian.org/debian bookworm/main amd64 Packages
Description: Utility scripts for internationalizing XML
 Automatically extracts translatable strings from oaf, glade, bonobo
 ui, nautilus theme and other XML files into the po files.
 .
 Automatically merges translations from po files back into .oaf files
 (encoding to be 7-bit clean). The merging mechanism can also be
 extended to support other types of XML files.

Please tell me it's not getting confused by the “-6” in the version!

lwindolf / liferea

Won't build on Debian stable. ./configure says “intltool too old” despite newer version being available. #1381