If you've used Sparx System's EA, you might know that its a quirky little program at times. I've come to love the power it gives me to document designs and interactions, even if I've had to give myself a crash course on UML just to get my head around it.
One thing I hate though is that sometimes things just don't work and its not obvious why its not working. When trying to create a Data Modeling Diagram to display the database objects involved in a proposed update, I found that the Data Types selection for my columns was empty: all the entries were missing. I was getting really frustrated until I checked on the table entity itself and found that Database for this table was not set. Once I changed to SQL Server 2000, my Data Type drop downs populated with the correct values.
In short, if you're using EA for a database diagram and your data type selections are blank, you need to check the database setting on the table itself.