You must perform the ArcFM Geodatabase Upgrade as outlined on the What's New in 9.3.1 page.

Flexible Geodatabase

The 9.3.1 version supports a flexible fiber data model which allows you to easily add features to your fiber data set and configure them to participate in your fiber network. If you would like to take advantage of this functionality, follow the steps outlined in the Configure Flexible Features section.

If you have already run the Fiber Stand Alone Conversion Tool and made your geodatabase compatible with Fiber Manager's flexible data model, you do not need to run it again. However, if you still need to make your geodatabase compatible with the flexible data model, follow the steps in the Upgrade to 9.3 Rev2 section.

Patch Panel Connection Report

The 9.3.1 release provides a new Flexible Patch Panel Connection Report. This report must be used with flexible features and may be used with existing (standard) features. To use this report you must perform the configuration. The previous Patch Panel Connection Report will continue to work as it always has if you choose not to perform these upgrade steps. (It will also continue to work if you do perform the upgrade steps.) The configuration outlined on the Flexible Patch Panel Connection Report page is optional.