Hi!
Could you please tell us, what kind of RDBMS do you use for the join?
Also do you use a the Flex Viewer or just the API?
Is it a dynamic/tiled or a feature service?
What you want works, at least I tried a File GDB with a dbf join in a dynamic layer with Flex Viewer 2.4.
I'd try to repeat the field names according to the Services Directory desription about the layer.
Example:
obj_attrbcbd.FEKVES (Type: esriFieldTypeInteger, Alias: FEKVES)
obj_attrbcbd.FOLDERT (Type: esriFieldTypeDouble, Alias: FOLDERT)
CIM.KER_ID (Type: esriFieldTypeString, Alias: KER_ID, Length: 3 )
CIM.HRSZ (Type: esriFieldTypeString, Alias: HRSZ, Length: 20 )
Here is some sample from my Flex Viewer's popup.xml:
<field name="obj_attrbcbd.FEKVES" alias="FEKVES:" visible="true" />
<field name="obj_attrbcbd.FOLDERT" alias="FOLDERT:" visible="true" />
<field name="CIM.KER_ID" alias="CIM.KER_ID:" visible="true" />
<field name="CIM.HRSZ" alias="CIM.HRSZ:" visible="true" />
Also I found a bug (suspect) in the popup window, where the contents of it disappeared (only the title and the horizontal bar were displayed) after the second click if I placed many fields into it, where it didn't had enough space to display in the popup box. I don't know if this is the same bug you experience as you also use many fields. Try to lower their number to less than 8 just for a test.
Could you please send a screenshot about it?
Andras