mathias@laptop $ emerge -pv drupal                                    /www/wiki

These are the packages that I would merge, in order:

Calculating dependencies
!!! All ebuilds that could satisfy "drupal" have been masked.
!!! One of the following masked packages is required to complete your request:
- www-apps/drupal-4.5.2 (masked by: ~x86 keyword)
- www-apps/drupal-4.5.7 (masked by: ~x86 keyword)
- www-apps/drupal-4.5.8 (masked by: ~x86 keyword)
- www-apps/drupal-4.7.0 (masked by: ~x86 keyword)
- www-apps/drupal-4.6.6 (masked by: ~x86 keyword)
- www-apps/drupal-4.6.5 (masked by: ~x86 keyword)
- www-apps/drupal-4.6.3 (masked by: ~x86 keyword)
- www-apps/drupal-4.6.2 (masked by: ~x86 keyword)

For more information, see MASKED PACKAGES section in the emerge man page or
refer to the Gentoo Handbook.