APC not in Module category Browse

I was manually compiling a list of 6.x modules from the http://drupal.org/project/Modules page.

After filtering modules by 6.x compatibilty, modules "APC" and "Imap Auth" only show when browsing by "Name".. not by "Category". Which category should it be in? Is the module is mis-identified to Drupal.org somehow?

Category summary as of Sept.27 14:20 (GMT -06:00)
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3rd party integration (3)
Administration (7) - only 6 modules are listed when this category is browsed.
CCK (1)
Commerce / advertising (1)
Content (2)
Content display (5)
Developer (5)
Event (1)
Javascript Utilities (2)
Mail (1)
Media (2)
Multilingual (1)
Security (2)
Taxonomy (1)
Theme related (4)
User access/authentication (3)
User management (2)
Utility (7)