Unflatten array

I am using xpath queries against an XML column like so:

annodb=# select id,xpath('//LastName/text()',content) from medlinexml
limit 10;
    id    |           xpath
----------+----------------------------
 12236137 | {Mikulicz-radecki,Freund}
 12305346 | {Ota}
 12332250 | {Bernstein}
 12255346 | {Novak}
 12255369 | {Kurzrok}
 12332284 | {Davis}
 12332297 | {Allen,Pratt,Newell,Bland}
 12305416 | {Goldstein}
 12305417 | {Seibels}
 12305424 | {Richardson}
(10 rows)

I would like to build a view where each id is associated with a text
representation of each last name.  So, the view would look like:

12236137  | Mikulicz-radecki
12236137  | Freund
12305436  | Ota

And so on.  Is there a way to do this without a pl/pgsql loop?

Thanks,
Sean