control file>object importer>blank value

[citrusstyle]

when importing FILE 1, the drop down (text: popup) value imported is "Box 1" - which is my expected result

FILE 1 for import:
<category name="Livelink Categories:Contract Categories:Customer Information">
<attribute clear="true" name="Box Archived"><![CDATA[Box 1]]></attribute>

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when importing FILE 2, the attribute drop down (text: popup) simply disappears...that's right, no more drop down box available - it's gone

FILE 2 for import:
<category name="Livelink Categories:Contract Categories:Customer Information">
<attribute clear="true" name="Box Archived"><![CDATA[]]></attribute>

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any ideas? it seems as if importing a "null" value into a drop down, it completly removes the drop down list from the attribute.....i mean, the attibute field name is there to the left, but to the right it's blank - no text: popup or nothing.

 

[citrusstyle]

is it because I'm using:

attribute clear="true"

?