hal ~ # layman -S
Traceback (most recent call last):
  File "/usr/bin/layman", line 23, in <module>
    from   layman.config            import Config
ImportError: No module named layman.config

hal ~ # layman -l
Traceback (most recent call last):
  File "/usr/bin/layman", line 23, in <module>
    from   layman.config            import Config
ImportError: No module named layman.config


after emerge layman && layman -l and layman -S

hal ~ # emerge -va mysql-administrator mozilla-thunderbird-bin

These are the packages that would be merged, in order:

Calculating dependencies /
emerge: there are no ebuilds to satisfy "=dev-cpp/gtkmm-2.8*".
(dependency required by "dev-db/mysql-administrator-1.1.10" [ebuild])