I checked with 1.1.0 German version WIN98SE: 645m19(Build8693) 

Steps to reproduce:

1. Start OOo with a new Writer text document
2. Open Additional new spreadsheet with Calc
3. go back to new Writer text document
4. Select Menu: "Insert - Field - Date"
   and insert a field with the actual date
5. Double mouseclick on field, so that Format-Window opens
6. Change with <Alt>+<Tab> to new spreadsheet
7. insert actual date (like 14.11.03) to 'A1'
8. Right mouseclick into 'A1'
9. select "Format Cells", so that Format window opens 
10. Change back  with <Alt>+<Tab> to Writer Document
11. Mouseclick on the 'X' of the 'Format Field Window' to close it
    Expected: window will be closed
    Actual: "bing"-sound, and window will not be closed (al other functions
             of the window will not work, too!)
             The Window can only be closed after the "Format Window" of the
             spreadsheet has been closed.

 
I checked some more functions an found, that for some other combinations the
second "Function Window" will block the first one.

Example: 
Open Menu: "Edit - Auto Text" in Writer document
Open Menu: "Format Cells" in Calc spreadsheet
Try to close "Auto Text" Window in Writer document: impossible!

But:
Open Menu: "Edit - Auto Text" in Writer document
Open Menu: "Data - Filter - Standard Filter" in Calc spreadsheet
Try to close "Auto Text" Window in Writer document: _it_works_

I think, those functions should all be independent from state in other OOo
documents.

Rainer