post-git conversion pecularity: all the tags have vanished!

[Nix]

This may be ignorance of git at fault, but, well, for all the trees that
Kristian just converted, gitweb shows that tags are present, but none
are pulled down by `git update' or `git clone'.

An older tree (tag list shown using Cogito: I'm trying to reduce the
conversion shock, Cogito is different enough for me for now):

loki 2498 /usr/packages/X11/lib/X11% cg-tag-ls
MODULAR_COPY    b5c6810e21be2e7ccfac8f0539d46bf75dbe50a0
XACE-SELINUX-MERGE      ac912988091574790c7cffbbc2c60b8c59f8fcef
XORG-6_7_99_1   922d0534154668918eaa09a36cc5cd53fc6b71b7
XORG-6_7_99_2   8ef91b9cc0a4a7b0361f6b40b3f735221c8272cb
XORG-6_7_99_902 1516173727005a87aa501e1ad708d72e6ae6e753
XORG-6_7_99_903 77c9e63a3abff1593ccbed249b2c3ae7f68e1833
XORG-6_8_1      58044c7087137ce2b521297dbb31934ccaedc94e
XORG-6_8_99_10  9b2e06fa262f23dbcbbccd42be6477e08a452268
XORG-6_8_99_13  7f99410bb9cc9f7cbbc2d43d8ad044771a6eec0a
XORG-6_8_99_14  99b59b83f126b4abb9da89f577a5b8147d543c25
XORG-6_8_99_15  97170c33f99761acd932f968e21d6d7664e7ba80
XORG-6_8_99_6   b39966d452127c992987d082f69321f950ae4c39
XORG-6_8_99_7   05e20c3bd8ac6b7e873607db73894486a4ac0519
XORG-6_8_99_9   f478497b5a3e9d6b92237e0f408c9f0f18108f52
XORG-6_8_99_900 c5ed936f28ce70c8932e33d67a6e06d140e35ba8
XORG-6_8_99_901 2b6beba295a6ff997dfe15a732c95ae6577fa735
XORG-6_8_99_902 32edbb1e9c5b7d1c6f8639dab85e5368d303df7f
XORG-6_8_99_903 490fbe2afb9ffc7057c0eb150f7cdd4d4fa8686c
XORG-6_99_99_900        fc605ac48bd7d675d6d04162a0f3bfebe27f2037
XORG-6_99_99_901        6289ecc26d1d505f395c59da744a9354d7aad2a2
XORG-6_99_99_902        8c9c30dac72aebd1a2c31a55a47c0ac11bc328db
XORG-6_99_99_903        3b7aa57994924be0dad693e837559d9ee900299c
XORG-6_99_99_904        b02ad9a8ec96e3c1027ca71289aeef5b8748e17e
XORG-MAIN       95b6462c70213b562c9d2b8726eda706edc9c456
libX11-1_0_1    33ca0b19cf631edc4b7d669861d01a6ba7a38d4e
libX11-1_0_2    e66e4746e8e0eba57345a8e682e63772f3c2adb6
libX11-1_0_3    2e73323fbcfaf80e335882e7290e4b314975a964
xprint_packagertest_20041125_base       11adfbe4676add2c1861bd3579283f78bcde9adc
xprint_packagertest_20041217_base       6d48a0387d171be7c7fe5e4bd9ef66754033f2f7


A newly-converted tree:

loki 2495 /usr/packages/X11/lib/libXvMC% cg-tag-ls
cg-tag-ls: List of tags is empty. See cg-tag.

But gitweb shows that the tags are there, so they're presumably present
on the server. (I'm checking out from anongit over the git protocol,
e.g. that tree was git://anongit.freedesktop.org/git/xorg/lib/libXvMC.)

I presume this was unintentional: judging by the libX11 tree the intent
is to convert the tags as well as everything else, right? Or do I need
to do something to convince git-clone / cg-clone to suck the tags down?