DOCBOOK-APPS: language specific character in PDF output

Is there anything I can do to get language specific character to be displayed
correctly in PDF output using Adobe Reader on Windowses ?

I use ł entity as second letter in my original name 'Wlodzimierz'. It
is rendered (xsltproc + 1.58) in xhtml to 'ł' and in fo to '&#x142' which
seems of course the same. When I previewed html rendering it is displayed with
correct character. When I created PDF using Fop and viewed that character with
Adobe Reader 5.0 CE (CE means Central Europe so polish character should be
supported). I have no problems with characters like 'Jérôme' for
example. I'm sure fonts on my computer has that letter installed and I'm sure
I have no separated Helvetica installed. Any ideas?

ABX