You can always write your own DTD-specific attribute filter, e.g.:

<xsl:template match="@*">
  <xsl:choose>
   <xsl:when test="self::attname_1 and
                   string(.) = 'default_value'"/>

test="count(.|../@attname_1)=count(../@attname_1) and
      string(.) = 'default_value'"

E.
--
W. Eliot Kimber
Professional Services
Innodata Isogen
9030 Research Blvd, #410
Austin, TX 78758
(512) 372-8122

eliot@xxxxxxxxxxxxxxxxxxx
www.innodata-isogen.com