Apple has identified an issue affecting Power Macintosh 4400/200 units using Mac OS 8.1. This is fully detailed in TIL Article 30627 referenced below. To correct these issues Apple has released the "Power Macintosh 4400 Update."
After this patch is installed, you will see "Mac OS 8.1 System Enabler 4400 Update" in the About this Computer window. If Mac OS 8.1 is ever reinstalled, the update would need to be reinstalled as well.
For additional information see the following TIL articles:
Tech Info Library Article 30627: "
Power Macintosh 4400: Mac OS 8.1 Installation Issue"
Tech Info Library Article 30720: "
Power Macintosh 4400 Update: Read Me"
This article can help you locate the software update mentioned here: