This problem is addressed in ArcGIS 8.1 Service Pack 1. See Related Information section to download this pack. If the Attributes dialog box is open, and you click the Split command to edit a complex edge feature, the Attributes dialog box will display the old feature. Subsequent mouse operations, like clicking the feature class node, will cause ArcMap to crash.
After clicking the Split Command, clear the selection and then select the split edges.
Get help from ArcGIS experts
Download the Esri Support App