gnucah won't load

[ED Antrobus]

In the archives I found the problem I'm having, but I could not find
the resolution.  I am running Mandrake 10.1 on a P4 1.8GHz with 1GB
RAM  GnuCash was installed from the Mandrake install disks when I did
a clean install of Mandrake.  The version of GnuCash is 1.8.9
When I try to run gnucash from the menu, I get the splash screen,
modules load, and then nothing.  I tried running it from console and
got the following error message:

The font "-adobe-helvetica-medium-o-normal--*-120-*-*-*-*-*-*" does
not support all the required character sets for the current locale
"en_US"
  (Missing character set "ISO8859-1")
  (Missing character set "ISO8859-1")
Fatal Error: gnucash_style_set_register...(): Cannot load fallback
font: -adobe-helvetica-medium-o-normal--*-120-*-*-*-*-*-*
 
I get the same error message for
"-adobe-helvetica-medium-r-normal--*_120-*-*-*-*-*-*" also.
How can I get around this/install the missing font?