There is a problem with v1.0.5 - project groups may be duplicated in some situations. We already have a fix for this issue and we'll release it soon. Until than you might use this fix:

1. Open /activecollab/application/modules/system/models/project_groups/ProjectGroups.class.php
2. Replace (somewhere around line 28):

return ProjectGroups::findBySQL("SELECT $project_groups_table.* FROM $projects_table, $project_groups_table WHERE $project_groups_table.id = $projects_table.group_id AND $projects_table.id IN (?) ORDER BY $project_groups_table.name", array($project_ids));

with:

return ProjectGroups::findBySQL("SELECT DISTINCT $project_groups_table.* FROM $projects_table, $project_groups_table WHERE $project_groups_table.id = $projects_table.group_id AND $projects_table.id IN (?) ORDER BY $project_groups_table.name", array($project_ids));

Thanks to Craig for brining this issue to our attention and sorry for the inconvenience.