Help here
Create a bleed for your publication
http://office.microsoft.com/en-gb/publisher/HP101208091033.aspx?pid=CH101778921033

Tips for preparing your publication for commercial printing
http://office.microsoft.com/en-gb/publisher/HA012189471033.aspx?pid=CH101736131033

Haloo

I have been able to print from a publisher booklet to a pdf with adobe giving
a 3mm bleed as follows:
Creating a 3mm bleed for a booklet in Publisher 03

First:
In booklet document,  format page image so it extends beyond the page
boundary by 3mm

Set up page and paper sizes
Page size ...
1.    On the File menu, click Page Setup.
2.    On the Layout tab, note the height and width of the current page size.
for an A5 booklet W=14.85cm H=21cm

Paper size...
On Printer and Paper tab.
3.    On the Name list, click adobe / pdf software
4.    On the Size list,
(a) select a paper size that is larger than the page size that you noted in
step 2.
(b) create custom as follows
On the Size list, click Properties.
In the Printer Name Document Properties dialog box, click Advanced.
On the Paper Size list, click PostScript Custom Page Size.
In the PostScript Custom Page Size definition dialog box, set the Width and
Height fields to the correct values  a few cm larger than your publisher page.

Click OK.

Now to check
your page is set to booklet A5
your actual image on the page extends beyond the screen page
your pdf is printed on oversized paper showing crop marks

Any good for you?

Bx