Variables not available to hook_menu during a site install using a custom installation profile

I can try to isolate this issue better, but wanted to report this anyway in case this affects anyone else or if anyone has a workaround/explanation.

I've a custom module that's pulled in during site installation by a custom installation profile. The module's hook_menu() makes calls to variable_get_value(). The hook_menu() calls that occur during the installation process can't seem to retrieve variable values. All the variable_get_value() calls return NULL, cause some non-fatal errors. After site install, the hook_menu calls work just fine and variable_get_value() returns the expected values.

While the module's hook_menu() is invalid during the installation process, subsequent calls to it after installation behave correctly, so the bug doesn't have a lasting affect except to trigger errors during installation.

I'll try to test this again in a clean environment (i.e. just one custom module looped into a custom install profile sitting in an otherwise only-core Drupal folder). In the meantime, returning early from the hook_menu in the event of NULL variables might just work.