What element to use to open an existing chm-file from a chm-file

Hi,

In our documentation we need to reference several existing chm-files, i.e.
made by other vendors. How do I go about doing this in my docbook-document.
When I use ulink (ulink url:"IDS5webUGbook.chm") I get "Page cannot be
displayed error" and this url:
mk:@MSITStore:C:\tools\xmltest\DocBook%20Help\htmlhelp.chm::/htmlhelp/IDS5we
bUGbook.chm

Do I need to do anything special to get Html help to show a chm-file
referenced from another chm-file?

Thanks,

/Kenneth

--------------------------------------------------------
Kenneth Johansson	Technical Documentation Manager
Sectra Imtec AB
Teknikringen 20		E-mail: ke-joh AT sectra DOT se
SE-583 30 Link鞿ing	Phone:	+46 13 23 52 00
SWEDEN			Web:	http://www.sectra.se